Are all beers kosher? If not, which beers are not?

Question

Specific brand names would be great in responses.

Answer 1

I think most beers are OK if they contain only grain, water, hops, and yeast.

This guy has a more specific answer for you.

Answer 2

Look at the label. Kosher beers will have either a "U" or a "K" on the label, depending on which group certified it as kosher.