Gridlock for iPhone allows custom icon positioning [Jailbreak]
Gridlock is an iPhone Jailbreak hack that will allow you to setup app icons on your home screen in a manner that doesn't interfere with your wallpaper or just let you create an awesome pattern -- the choice is yours. It is easy to use, all you have to do is hold down on an icon to make your apps jiggle like you always do and then move them around anywhere you want.
That's it, no app, no settings, just click and drag your icons anywhere! Best of all it's just $0.99 in Cydia, thanks Chronic Dev-Team member chpwn!