A few come to mind....
I put some of the louder games in a couple of categories. Eardrum splitting noise you can feel and hard to hear your neighbor noise:
Here are some of mine in no particular order:
2003 Bama/OU - This was an easy pick.
1982 Penn State in Legion Field - I was barely 8 at the time but can distinctly remember sitting in the upper deck at this game. This is the year we beat them 42-21 and blocked 2 punts, 1 of which occurred when the safety blocker accidentally backed up to far and the punter kicked it right into his rear end. The place was shaking it was so loud.
1989 Bama/UT at Legion - Lot of loud moments in this one.
1991 Bama/UT at Legion - This one stands clearly out in my mind as one of the loudest games I ever attended. The noise level was high throughout the game.
1992 Bama/Miami - I wasn't at the game but I've heard it was a party.
1995 Bama at Auburn - I've been to Kneelin once, UGA, LSU, and Florida, but as much as I hate to admit it the Aubs take the atmosphere level to another level when we visit. I never want to compliment the Aubs, but you simply got to give it up to them strictly from a noise standpoint when we visit. The place gets ridiculously loud and the Aubs do a good job of yelling in unison to get the decibel level up there.
1999 Bama/MSU - This game stands out as well. This game was another great example of what BDS can be when people are more interested in making noise than asking the people in front of them to sit down.
2002 Bama/UGA in BDS - The Peprah int. returned for a score has to be one of the loudest single moments in BDS history.
1995 Auburn at LSU - I went to this game with a close Bama friend and 2 close Auburn friends of mine. We stayed with my Bama friend's girl friend at the time who was from Baton Rouge. We got free tickets in the LSU student section. To this day I've never seen fans cheer over so many things in my life. The stadium was literally cheering when they were announcing the halftime stats. The thing the LSU's band does as the team is about to run onto the field may be my favorite introduction in all of college football. (i.e. The "duh, duh, duh, DUH" thing).