beer in GR
Founders is great, but like the BOB, go there early (like before dark) unless you like elbow-to-elbow crowds and college hooligans bumping into your glass. Founders has a huge selection of huge beers, very strong, very good, and occasionally an experimental that misses the target.
HopCat is right in the middle of downtown, best beer bar in the country in my opinion-- dozens of drafts from around the world, specials constantly, Tues-Thurs from 4-6PM you get a huge burger, crack fries and a draft for only $6.
The other brewpub I'd suggest is called the Hideout, small brewery north off Plainfield. Great beers, they also lager a few, and always consistent quality. Cool place, great beer.
If you don't want to drive out of downtown too far, Sammy's in Eastown has a good selection of single bottles, or Art of the Table on Wealthy St., or Martha's Vineyard on Union and Lyon is awesome too.