You know you just can't be restricted by wires when you're
jamming on your keytar. Now there's a solution: Classic MIDI Works'
MIDIjet Pro not only does wireless, but gives you a full 500-ft. range
running on just 2 AA batteries. (Non-pro MIDIjet gives you fifty feet.)
It works via 2.4GHz range with low latency.

This, of course, begs the question: why haven't we seen any compact
wireless MIDI devices? The MIDIjet is fairly big and clunky — more
than I want to attach to said keytar. How about Bluetooth, which is
also 2.4GHz, for short-range control?

Pricing / availability not yet available on the Pro models; the original (non-Pro) kit is US$375. (via synthtopia)