A mish-mash team of superheroes, who don't really have anything in common except that they fight as a team. They probably don't share philosophies, world-views, moral codes, or origins; they may or may not even like each other very much (or at all). The only thing that matters is that the members show up when they're needed.
A Super Team may all live in the same place (if they do, the audience can expect occasional friction from that). There is often an overarching organization they've all been recruited by, or work for, to help explain why such different characters band together despite their differences.
If the team does get all "I'll do anything for you man! You're like family to me," then they've become a Badass Crew, and probably have to come up some Badass Creed and the like. If they're actually related, they're a Super Family Team. If the team all has related powers and color-coded outfits, you're probably looking at a Sentai.
Contrast Legion of Doom and Villain Team-Up.
The latest incarnation of the Seven Soldiers stretches the very idea of a super team to its limits; In order to keep the new Soldiers from being killed by the Sheeda like the previous team, they have to be sure that none of them ever meet each other. Seven people who don't know one another even exist have to accidentally work together to save the world from a threat they aren't aware of.
In "Under the Hood" (a book-within-a-book written by the first Nite Owl chronicling his time as a superhero) Nite Owl said that "it takes an extreme personality to put on a costume and fight crime and the chance of eight such personalities getting along is a million to one." Then, of course, there's the fact that after the Comedian tried to rape the first Silk Spectre, the Minutemen began to distrust each other and subsequently collapsed.
Later when Captain Metropolis (a member of the last super team, "The Minutemen") tries to form another Super Team, "The Crimebusters", the Comedian denounces the whole idea as bullshit, claiming Captain Metropolis is trying to play "Cowboys and Indians". He further explains that whatever heroic deeds they accomplish will be undone byan impending nuclear war. Rorschach agrees, complaining that "a group this size seems more like a publicity exercise,", adding that "it's too big and unwieldy." The first meeting of the group is the last because of this.
The Invincible Universe has several, Punch Clock Heroes Capes Inc, the The Guardians of the Globe (two versions thereof) and the Teen Team (disbanded when most of it's members got too old)
The Seven in Garth Ennis' The Boys. They are a super team who aren't together to fight greater foes or even because they LIKE each other. They're together purely because they make more money of merchandising that way. In fact none of them can stand each other.
Kick-Ass 2 sees Dave joining a group of like-minded superheroes called Justice Forever.
The somewhat obscure Cla$$War by Trevor Hairsine and Travel Foreman features Enola Gay, yet another Justice League pastiche.
Another DC team, the Inferior Five poked fun at the concept of a team consisting of people who save the world by themselves pretty much every other day of the week. The Five were all so weak that they wouldn't be able to do anything if they didn't work together.
Many chapters of Accidentals abound with teams. The first government sanctioned team was formed by the Nazis during WWII. British and American government sponsored teams were formed as a response.
Team Kimba, of the Whateley Universe. They're only teenagers at Superhero School Whateley Academy, but they've already beaten superpowered ninjas from the Yama Dojo, the Necromancer and his team The Children of the Night, and Lovecraftian horrors. Plus, they're not supposed to be superheroing, so they keep getting detention for this stuff.
Most of the students at Whateley are on training teams or are in groups that can put up some sort of superfight in a pinch, the chief exception being the Underdogs.
Most of the campaigns in the Global Guardians PBEM Universe were based around a Super Team of one sort or another. Notable exceptions were the Big Easy campaign and the aptly titled Solo campaign, both of which were about a single hero, and the Hyperion Academy and Venture Institute campaigns, both of which were about schools for superhumans.
Many, some lasting longer than others, in Marvels RPG, including the Ultimates, the Avengers, Generation X, the Crusaders, the Guardsmen, even if some are starting to become Bad Ass Crew or True Companions.
Young Justice features a group simply named "The Team"- although they have quite a lot in common with the Teen Titans, whose name was already taken by another cartoon. In universe, the reason for this is that they're a covert ops group, and there's no need to bring extra attention to themselves.