Jeti Duplex, Multiplex M-Link, Graupner HoTT, Futaba, JR DMSS, and Spektrum (using spektrum adapters).
These sensors offer excellent features and small packaging. They offer some really nice items like magnetic, brushless or optical RPM sensors, 400 amp current sensors, or the super cool TEK (total energy compensation) vario nozzle that takes elevator inputs out of your vario data.
The Unisense is really a neat product that offers: voltage, current, power, wattage, watt hrs, brushless motor RPM, altitude and vario. That is a lot in a tiny package!