My favourite themes for my ipod touch you need your ipod to be jailbreaked and have cydia the themes are :
10 - Slick Shelves
9 - Cherrinio
8 - Hackintosh
7 - 8liasTAG
6 - Buuf2
5 - Leopard Theme
4 - Black Label
3 - Vista Ultimate
2 - Matte Nano
1 - ChocoMilk