I been messing around with the arduino now for a couple of weeks and really find them usefully and easy to us (well the basics) and all you need is a computer and little knownage. The issue i found is there was very limited info o how to get them to work with are RC units.
So with a couple of very knowledgeable people (not me :) ) we found it would be a good idea to set up a forum just for the use of Arduinos with RC, with how too and for people to ask questions.
One example i've got working is with my robbe 8 ch mutliswitch so instead of paying £50 + for a robbe unit or a cheaper clone, i got it working for a fiver :)
If your interest or wanting more information on want can be done, please pop over and have a look.