Eyeshadows! Because I can't even remember the last shadow I bought that wasn't Mac. Since my first Mac e/s I didn't buy one single e/s from another brand!
But lipsticks are close, because I'm not allergic to them. Other lipglasses I'm not allergic to are easy to find, eg my Spell glosses are great, they feel so much better than Mac glosses.
I would cry about my Brit Wit cremeblush, though.