If all you want to do is light up some leds or something similar
you can do this without any microcontrollers at all with a pair of these chipshttp://pdf1.alldatasheet.com/datasheet-pdf/view/109184/SAMHOP/SM5172.html
They simply take a ttl input like a pushbutton, encode the pushbutton into a data stream which goes to the transmitter
and a similar chip takes the data output from the receiver and re creates the ttl level, so you could connect the leds directly
to the decoder chip.
In their most basic mode , they can transmit 4 bits of data so that would allow 16 leds to be controlled.
The chips cost around $2 each.