I've been haunting Zablozki's since about 2004. One thing you can count on is decent prices on the brews. The usual suspects on tap: Stella, Yuengling, Brooklyn Larger, etc. And if you're on a starving artist's budget, you can get the trusty old PBR can for about $2. There's always good music playing, friendly barstaff, free wifi, and usually a friendly dog walking around greeting the patrons. There's a pool table in back, and a garage-like glass door that opens in warmer weather so you can people watch. It does get a little crowded on the weekends, but so does all of N 6th St., so beware, you're not going to get a seat or get served as quickly as you would on say, Tuesday night.
Pros: Quiet during the week, free wifi, cheapest beers in NYC
Cons: Overrun with Hipsters on the weekends.