What are your favorite beer cocktails?

I have been wanting to try out some new beer cocktails, and wanted to see what your favorites are. Mine are shandy, black velvet, and a makeshift margarita.The makeshift margarita is:1 can of Limeade concentrate 2 bottles of Mexican beer (12oz Modelo Especial) 10 ounces tequila http://www.reddit.com/r/cocktails/comments/3gb857/what_are_your_favorite_beer_cocktails/