The jailbreaking community has brought all sorts of interesting tweaks and hacks to iOS devices. Lion Ultimatum is functional theme for jailbroken iPhones that attempts to completely replicate the OS X user interface, not just with icons and a background, but with "fully usable Finder menus, stacks, launchpad, a scrollable dock, draggable windows, mission control, dashboard, and a customizable lock screen."
Lion Ultimatum is a free install for jailbroken iPhones. Lifehacker has installation instructions for those interested in trying it out.
It is, however, more useful as a proof-of-concept than anything else, and shows why Apple redesigned the iOS user interface from the ground up to be touch-compatible, rather than simply shoehorning the OS X interface onto a smaller touchscreen.
Top Rated Comments
It looks very awkward for a touch-based input device but it is a fantastic proof-of-concept.
It also demonstrates the amount of passion developers have for the iOS platform. I love it.
How do they impair productivity or battery life? If you don't like them you don't have to use them so they can't possibly impair your productivity, and even if you do use them what are they doing that will impair battery life?
I agree about missing Expose though.
I would love to have this on an iPad... you'd have a full desktop resolution... that'd be pretty sweet. iMacbook
Anyone who has used a remote desktop tool on iOS already understands why you need a totally new interface for touch.