Two year olds love stickers. My two year old is getting better and better with them. We actually have been low on our sticker supply and my older kids are not much into stickers so my baby hasn't gotten to play with them lately. My sister in law sent her a sticker book and she loves it. She doesn't use the book the way it is intended however. She likes to place the stickers on herself or other things. Oh the creativity of letting her do this is wonderful.
A two year old after dinner -- messy food on face, marker on face, stickers on body.