If I had to choose one, it would be the one against Dinamo Kiev in the 93/94 CL (4-1). Perfect playing. I've never seen anything like that. Another link: http://www.youtube.com/watch?v=fgR1iSzIeJ4
This has been surely done to death already, but I'm in a nostalgic mood since nothing this season has given us much of a thrill... Most dramatic game involving Barca is 1997 Copa del Rey vs. Atletico Madrid, a game with more twists than a pretzel factory and then... PIZZI!!! QUE BUENO QUE VENISTE!! SOS MACANUDO!! http://www.youtube.com/watch?v=JIShXXWDr8A The only negative point is to see traitors-to-be Figo and Ronaldo chipping in for the cause. But what a game.