uAvionix introduced their echo and SkyFY ADS-B units here at Sun n Fun. The echo box is an ADS-B in and out unit that transmits on 978 MHz, which is fine for planes in the US below 18,000 feet, which covers most Experimentals.
It works with any mode C or mode S transponder and requires no hardwire connection to your transponder to work. It needs a GPS/WAAS source for position, which can either come from your approved GPS or from their SkyFY box. It sends traffic and weather to a number of devices such as an iPad with ForeFlight.
The echo box costs $999 and include required antennas. The SkyFY box costs $500. For the show they are offering both units together for $1399. Most owners should be able to do the installation in one day.