lolol. we have gone waaaay off topic now. ;)
Back on, is this the one:
You should do an AMA!
The documentary that best captures the spirit that you're talking about is The Year Punk Broke, which just came out on DVD with some previously unreleased scenes. It covers Sonic Youth's brief European tour in the summer of 1991, along with Nirvana, Dinosaur Jr., Babes in Toyland, and many others. Another good one is Hype!, a 1996 documentary about the Seattle scene.
That 1990 to 1991 period was really magical. Watching some of these great bands that were on the verge of superstardom playing small venues is just something to behold. My favorite example of this is Nirvana playing in England in October of 1990. Just look at the crowd!
The coolest thing about the Crisco Twister video (from 20 years ago this Friday) is that after the show, Nirvana realized that the audience was restricted to people 21 years old or older. Since they had an off day on their tour the next day, they immediately scheduled an all-ages show for the same venue for that day. Of course that day was September 24th, 1991, the exact same day that Nevermind was released.