Possibly the only thing to do for people between the ages of 20 and 50, there are over a dozen bars to choose from packed into a couple blocks. Since there are so many bars and such a small population to use them, competing establishments have some ridiculous drink specials to lure the crowds.
BJ's is the main hub for live local music, Fredonia rock bands, Indie, etc. Not to mention specials for every night of the week. Tequila Tuesday Dollar Shots, Quads on Thursdays 4 shots, 4 dollars, Saturday dollar pints from 3-8 and free hot dogs, as well as dollar well drinks and bottom shelf shots all night long.
Heenan's Pub is a favorite for many locals because it is a traditional Irish Pub. You can find your Irish family crest on a map next to the dart boards. 5$ pitchers and friendly bar tenders make it a good time for all. If you frequent the bar enough, or if a bar tender appreciates your compliments or tips they'll flip you a wooden Heenan's coin that is redeemable for a free drink.
Liberty's is a bar located in a residential area. Students hardly ever go near the place, but usually the student bartenders are so happy to see someone their age that they will give you some great deals. Everybody smokes indoors and there is a big room with pool tables/games/etc.
The best place for specialty beers and micro brew, as well as a rooftop patio, live music, and great food. Ellicottville Brewing Company EBC is the place to be. They feature many house beers and this is the place to purchase growlers. Bring them back for a cheap refill anytime.