Although I have seen this kind of thread pop up from time to time, it is fun to think about... With that having been said, I have heard that the crowd at the game in Gampel against #1 Texas in 2010 was rocking the joint early on and for the entire 2nd half.
But the best one I ever attended was amazingly at the Hartford Civic Center - January 20, 1990 vs. Georgetown. If Georgetown won that game they would be voted #1 in the country that next Monday. And everyone that showed up that night knew it. I had the great fortune of announcing that game courtside for WHUS. And from even 10 minutes before the opening tap, the place was electric. And as we built the early lead, it grew louder and louder until it reached a crescendo as we made it 14-0 in the first 6 minutes. Then of course Georgetown came roaring back... Mourning talking trash into Henefeld's ear on the foul line virtually right in front of me in the first half... and then Henefeld coming out and having the best 2nd half I ever saw a UConn player have in such a big spot. Hitting clutch 3 after clutch 3, until we finally put them away in the last minute, the crowd going crazy... Johnnie Gwynn's hyper tongue flick as Henefeld was sinking the free throw daggers.
The game that unofficially put UConn on the map, and still my favorite regular season memory of all time. And thanks to tcf15 you can go to the website he set up and watch that game in its entirety. I personally recommend that you do... it is a fun, rollicking and yet gut-wrenching game to watch even now, over 27 years later. And the best part is, the good guys prevail in the end!