Karl,
I drank enough PBR in college to float a battleship on. Back then the bar I hung around in sold two $1.00 longnecks: Pabst Blue Ribbon and Lonestar. And I hate Lonestar so I drank my fill of Pabst. I still drink it from time to time. I'll even drink Schlitz if I can find it. They're still making it and I'm told they've gone back to the original recipe.
As a homebrewer and a craft beer drinker, my favorite these days is probably decent English ale. Nothing fancy or too hoppy. If I don't have anything on hand, I do drink a lot of Sam Adams and Coors Light.
I will admit though, being something of an occasional opportunist , I have learned that often times the best beer can also simply be a cold beer. And if not a cold beer, a free beer.