Unsigned positive reps. Yes, I know it's all up to the repper & that I should just be happy with the thought & the comment (& I am), but darn it's annoying when you can't figure out who it is that repped you!
Of course unsigned negs would be much worse, but in a different sort of way.
edit: of course it's the height of irony for me to receive an unsigned *snicker* for this post...& the height of cruelty for the repper to do such a thing. 