It’s wasn’t so long ago that RC transmitters, at least ones worth owning, were expensive pieces of gear. Even more recently than that, the idea of an RC transmitter running an open source firmware ...
So you've already outgrown Arduino's most beginner-friendly board, the Uno, and are looking to move on to bigger, more exciting projects. In that case, the Nano family might just be what you need.
Before there were smartphones, there were personal digital assistants like the Palm Pilot, Handspring Visor, and Compaq/HP iPAQ line of devices. And before those, there were really basic PDAs, like ...