Infinidock is a new project by chpwn. It enables you to add up to 10 icons on your dock unlike the normal amount of 4. When you add more then 4 icons you can scroll horizontally through the icons. It is available through Cydia for $0.99, so it can only be used on jailbroken iphones.

You can simple drag and drop the icons into the dock and the dock will grow to accommodate them. At the moment they are working on a update so infinidock supports Stack.

source: modmyi