This small RF pixel controller is probably the cheapest on the market. Its best use is probably as a pixel string tester!
Can control up to 2048 pixels and takes from 5VDC to 12 VDC.
In order to use this controller, you’ll need a power supply with external DC Jack connector (or you can cut the connector and plug it directly to your favorite PSU with terminals).
Includes a xConnect pigtails connector on pixel’s side.