Springtomize - Tear down the walls
Five Icon Dock - Tweaks the dock of your jailbroken iPhone so that it can fit five icons instead of four.
Five-Column Springboard - Adds a fifth column to the homescreen of your jailbroken iOS device.
Infiniboard - Vertically scroll your home screen pages!
Five Icon Switcher - This puts more icons into the iOS4 multitasking bar, instead of the usual four.
Infinidock - Infinidock is the ultimate dock customization tool for jailbroken iOS devices.