Please don't list this on a work's page as a trope. Examples can go on the work's YMMV tab.
Tear Jerker: Stein's Gate
The second half of episode 16 delivers them one after another:
In a heartwarming example, Mayuri realizes who Suzuha's father is: Daru. Daru and Suzuha share a moment before Suzuha departs in her time machine to set aside an IBN 5100 from 1975 for the lab to use.
The lab receives a letter from Suzuha a few hours later thanks to The Slow Path. The time machine hadn't been fixed properly; Suzuha suffered a concussion upon arriving in 1975 and didn't remember her mission until 2000. In the letter Suzuha begs Rintaro to prevent the damage to the time machine from happening, so that she can go to 1975 earlier. Rintaro finds out a few moments later that after writing the letter, Suzuha committed suicide out of Amnesiac Dissonance. Rintaro sends a d-mail to the past as Suzuha requests, but as Mayuri points out, this will totally negate the dear friendship they had all formed with Suzuha.
Shippai shita, Shippai shita, Shippai shita, Shippai shita! And the line scrawled down the page at the end. That got this troper good.
The dub version is just as devastating.
Suzuha: I failed. I failed. I failed. I failed. I failed. I failed. I failed...
Despite undoing their friendship, it turns out that the d-mail worked.
How about a few episodes later when Okabe realises that to save Mayuri, he has to undo the D-mail that prevented Kurisu from dying? He spends the next couple of episodes (and a few more time loops where Mayuri dies) trying to Take a Third Option - and ultimately failing. The ultimate Tear Jerker comes when, having during this spilled the entire story to Kurisu herself, the two of them conclude that the only way to save Mayuri is to delete the D-mail; before contacting Daru to crack SERN's database and do just that, Okabe finally confess that he loves Kurisu, who responds by kissing him. Kurisu then apparently leaves on the train so as to avoid having to say goodbye to any of the others... only to run back to the lab and confess that she loves Okabe in return just as they are deleting the D-mail.Manly Tears all round.
It's even worse since she was interrupted. All she managed to get out was "I'm also in -" before he time travels. It's pretty obvious what she's about to say, but it's just a killer that she wasn't even allowed to say it properly.
And from that same episode: "You can cry for yourself now."
Basically most of the later half of the show.
Episode 13. You won't be able to hold all your emotions.
Episode 17 when we find out just what Rumiho sent in her D-mail.
Episode 21 where Rinatro tries to prevent Mayuri's death without returning to the original timeline only for her to die again when she prevents his death. As she dies in his arms yet again, she reaches up to the stars and says she's glad she was able to be useful to him.
Also, while at her grandmother's grave, when it is revealed she can hazily recall each time she's been killed.
Before the first half ended, Okabe revealed that he only created the Lab because he couldn't make friends, and that now, he has a lot of friends. Just a little tinge at my eyes, promise.
His own nickname, and calling Mayuri his "hostage"? Both were inspired by watching a TV show as a child with Mayuri. His mad scientist persona? He created it subconsciously to entertain Mayuri. Literally every action we see him do in the game and anime are all for the closest and longest-lasting friend he ever had, and she dies! .... more than once, to him!!! God...
All of the alternate endings. These range from bittersweet to plain downer endings, but it does make the true ending that much sweeter.