has eny one converted a eeletric free flight to rc?

Yes, it's been done often. But not by me!

- Jeff

Thousands of pilots have done this. Typically the Herr-kits were used a lot, have a Herr-Pitts myself. This machine performs VERY nice as RC.
Earlier we had to use the tiny geared Wes-Tech or IPS-motors ( http://www.mft.nu/driv/sma.htm ) but today there are some small nice brushless-beauties available. I have cheap Penta receivers (3,4 gram, 5 channels) and the smallest Waypoint servoes (Nuke) which are 2,8 gram. None of these parts are expencive, but there are xtreme lightweight things on the market and these gadgets cost a lot...
For indoor the Penta/Wes-combination can run on 1S LiPo