Interesting enough there is a device from Intel called RealSense that looks very much like a Leap Motion, the R435, sold for 275$ which purports to add a finger tracking interface to any current UI with a simple driver install and no changes to the UI code. It would appear that this is a step in the right diection.

Furthermore, the RealSense SDK is apparently open source, as opposed to what Ultraleap has, which seems rather closed and/or expensive.