Don't you sometimes wish to hide your dock? If you do, then SwipeDock is the perfect tweak to do this for you. Search for it in Cydia under the ModMyi repo.
With SwipeDock, you can simply hide your dock by swiping it with one/two/three fingers. In return, you can show it in the same way.
There are some other options like hiding the dots or make a double row dock. For me I found the double row annoying because the icons on your springboard will shrink.