Anything with triangles, curved seams, Y-seams, or that involves paper piecing.
Pretty much everything but squares and rectangles, at this point! But I'm getting better and better with each quilt.
SOME day I want to make a Double Wedding Ring, a Storm at Sea, and one of those awesome Judy Niemeyer (I think I misspelled her last name) PP quilts. I'm just barely brave enough to try a Drunkard's Path now...as soon as I finish a few gifts I have in progress, that's my next Big Adventure.