"Scott's Tots" has a bittersweet one. Near the end, Erin tries to cheer Micheal by telling him of the increased graduation percentage of the class. So even if he failed, he did arguably help the children.
In the early S2 episode "Sexual Harassment'', Jim feels the usual awkwardness when Pam, Roy, and Pam's mother are together in the office, getting along. After Roy leaves, however, he does overhear one exchange from his desk that gives hope that his feelings for Pam are not as one-sided as it seems to this point in the series:
(in whispered tones)
Pam's Mom: So which one is Jim?
Pam's Mom: I just wanted to know.
In "Crime-Aid", Bob Vance sets off a bidding war for a single hug from Phyllis, in order to raise money to pay for people's stuff which has been stolen from the office. David Wallace, Dwight, and Andy all join in. Phyllis, who puts up with crap from everyone, including Dwight, just sits with a delighted look her face. Everyone pulling together was terrific, as was Phyllis finally getting a boost for her self-image. It ends with Bob paying $1000 for a hug from his own wife, just to cheer her up and help out the company he shares the building with, so its a CMOA for him as well.
'"Employee Transfer". Michael is deeply depressed after splitting up with Holly. Darryl, who is often enemies with Michael cheers him up by inviting him to sing a blues with him in his car as they travel home. Doubles as Tear Jerker and Funny (Michael isn't an apt learner when it comes to singing blues).
"Lice". After all the shit she has been through, Meredith finally gets the respect she deserves as a single working mom. And that comes from Happily Married Pam of all people.
Pam's marriage however is under strain recently with Jim away in Philadelphia working at his new business.
Even after years of verbal abuse from them, Kevin still considers Angela and Oscar his friends and admonishes Senator Lipton for exploiting them for his political campaign.
When Jim and Pam find out that Pam is pregnant in "Company Picnic", and the whole scene is silent but you know what is happening just by their reactions.
In "Niagara: Part 2" when Pam accidentally tears her wedding veil, Jim cuts his tie in half so they're "even".
We find out that before the church wedding, Jim and Pam snuck away and got married on the Maid Of The Mist.
The ending of "Goodbye, Michael". Hell, the entire episode is rather heartwarming.
Jim, in Last Day In Florida, decides to do anything that he can to stop Dwight from going into the conference and getting fired. And by that, we mean wrestling him to the ground and blocking his path outside the room, getting both of them hurt a few times in the process.
The look on Jim's face when he stops at the door at the end of the hallway is heartwarming in itself. He turns and looks over his shoulder and you can feel him realizing he really does not want Dwight gone. Cue tackle.
Special mention has to be made to "Business School", where Pam has spent the entire day at her art show unsatisfied as no one from the office as come to offer strong support for her work (the only familiar faces to show up were Roy and Oscar, the latter of whom criticizes Pam's work with his boyfriend). Enter Michael, who, after dealing with the conflicts of Ryan's business class, responds enthusiastically to Pam's work, particularly the drawing of the office building's exterior.
Michael: I am really proud of you.
Pam: (hugs Michael) Thank you.
A moment that goes from Tear Jerker to funny to this is when Michael, at the end of his rope trying to manage his finances with his unemployed girlfriend and a bad house investment, decides to declare bankruptcy and does so by stepping out of his office and stating "I DECLARE BANKRUPTCY!!" Oscar, one of the accountants, comes in and spends a while trying to help him with his finances.
In third season's "Branch Closing", when everyone in the office learns that they're keeping their jobs because it is the Stamford branch that is closing and not theirs, Kevin and Angela, of all people, immediately hug each other out of relief, with the huge smile on Angela's face particularly telling.
Another hug in the next episode, "The Merger", when Jim finally returns to Scranton. Pam has been acting giddy about it all morning and the look on her face when he walks into the office is priceless. He first tries to make a joke about it ("Hi, I'm Jim... I'm new here") but Pam just Glomps him.
The end of season's 3 "The Job". In a talking head, Pam expresses her regrets about how it never worked out between her and Jim, but that she's OK with it and that she knows they will still be friends, even if he gets the job in New York City. As she is saying all this, however, we see Jim cancelling the job interview and driving back to Scranton—alone, without Karen. He barges into her talking head interview and asks her out for dinner. Completely surprised, Pam automatically accepts and Jim says it's a date. Cue Pam turning back to the camera, positively beaming and with tears in her eyes.
"Back from Vacation": Pam is crying in the hall as she has just helped further Jim and Karen's relationship by talking some sense into Jim. Sure, I Want My Beloved to Be Happy, but it still hurts like hell anyways. Dwight walks in and sees her crying. His first reaction?
Dwight: Who did this to you? Where is he?
He then sits down besides her and puts his arm around her. It's awkward, his last remark doesn't help ("So you're PMSing pretty bad, huh?") but hey, it's the thought that counts.
On a similar note, as soon as Phyllis admits that she thinks Bob might cheat on her, Dwight immediately stops what he's doing and gets down on her level to listen to her. The next shot we see of them is entering the party room, and Dwight dances with her despite him saying normally he wouldn't. Its obvious he's trying to cheer her up.
The whole office dancing down the aisle at Jim and Pams wedding
Andys 12 drummers drumming for Erins secret santa gift
The 'Bring Your Daughter To Work Day' episode, where Michael is initially uncertain about being around the kids the other workers bring in, but then proves capable of keeping them entertained across the whole day and thoroughly enjoys his time with them.
After Brain got fired for interfering with the documentary, the rest of the documentary crew decide to do likewise and help Jim perform a romantic gesture to Pam. They've clearly grown fond of them if they're willing to jeopardise their careers.
"Livin' the Dream: Part 1" ends with Dwight finally getting his longed-for Regional Manager position, at least in part due to a recommendation on his behalf from Jim to David Wallace. After the promotion is announced, Jim congratulates Dwight, who thanks him...then orders Clark to "get out of Jim's seat" across from Pam. Then he names Jim as Assistant (to the) Regional Manager.
Part 2 has Andy say goodbye via his version of "I Will Remember You". The song is so touching that some of the employees rethink their opinions of him.
Dwight's proposal to Angela in A.A.R.M.
In the same scene, Dwight finds out Philip really is his son. His reaction is just so amazing.
The ending with the cast watching the first episode of the 'documentary'.
Several in the "Finale" episode:
Michael showing up for Dwight and Angela's wedding to be Dwight's "Bestest Menschen". This time he's finally acting like an adult and Angela - the one who probably disliked him the most - is happy to see him. His name wasn't even shown in the credits. The writers broke the fourth wall and pranked us all.
The reveal that he and Holly have several children, which he is so excited about that he owns and pays for two phones just to hold all of the pictures he shows people.
Erin's longlost parents showing up at the panel session.
Stanley has retired to Florida and carves wooden birds, and it's clear that Phyllis misses her old desk-mate and friend. Later in the episode, Phyllis shows off the little statuette that Stanley carved for her as a gift — a small likeness of Phyllis with bird legs — and by the tone of her voice, you can tell how much it means to her. She even stresses that, buried beneath all the grumpiness, Stanley is really a very kind man.
Jim and Pam go into Dwight's office to give their resignations, Dwight immediately cuts them off and fires them. When they try to stammer out an explanation, he reveals he did it so they could have severance pay.
Jim's last prank of the series, Guten Pranken, in which [[spoiler:he uses his knowledge of all of Dwight's quirks to give him the best wedding day he possibly can.]
Toby had it pretty rough in the end, but his spirits pick up a little when the office crowd invite him back to Dunder-Mifflin for one last party.
All of the final speeches. By this point, all the characters know that they'll go back to being nobodies the next day and decide to make the most out of their time.
In a deleted scene, the employees realise that the most senior member of their group is the office plant. They decide to take it out and plant it in the sun, so that it can have the freedom that so many of them have gained.
After struggling for years to find a foster child, Nellie gets Ryan's.