Chinese company Allacax is now offering a wireless flash option for the Sony NEX cameras that use the proprietary flash connection (NEX-3, NEX-5). The unit consists of a small wireless transmitter that fits into the camera's top accessory slot, and a larger receiver that has a flash hot shoe.
The unit is not TTL, it only triggers flashes (up to a 1/160 sync speed), but it's also only US$45 and could be handy for triggering remote studio lighting with a low-end NEX. You have a choice of channels over the 2.4Ghz radio connection, and claimed reception is 100m (300').