For those of you who know me, you know that i'm rather into YAC. It uses a completely different algorithm from Bitcoin and Litecoin (and all of litecoins clones). Its known as Scrypt-jane or chacha.
Anyways, since its release, yac was a CPU only coin. Recently a GPU mining app (modified CGminer) has been released for YACoin.
Get it here!
I personally mine on yac.ltcoin.net, and I have had nothing but good experience with them.