Winterboard - Give your iPhone or iPod Touch a graphical overhaul!
LSrotator - LSRotator lets your iPhone's/iPod's lockscreen rotate according to your device's...
Dreamboard - DreamBoard lets you take control over the homescreen of your jailbroken iPhone.
Cylinder - Sexy homescreen icon animations
Lockinfo - You can find this app in Cydia - Tweaks.
Springtomize - Tear down the walls