This is a bit of self-promotion, but personal biases aside, I really do love the sticker pack I made. It's a ton of phases (over 150) that look like rubber stamps. They can be sent alone, peeled, then rotated or scaled and applied or my favorite is to send them with screen effects like "slam", "loud" and occasionally "lasers". Check it out and let me know what you think.
http://bit.ly/StampPack
http://bit.ly/StampPack