Harpoon IPA. No question.
A couple of days after my 21st (which was on Thanksgiving

) my boyfriend (now husband) took me to a bar in Boston that has 110 beers on tap. He offered to buy me a yard of any beer I wanted. So I got a few of those 5-oz samples, and eventually decided on a yard of Harpoon IPA. (Now you know why I married the guy.

)
My other fave is a black and tan - Guinness and Bass. A half-yard or a yard of Guinness and Bass is quite an impressive sight.