I was looking over the R/C Receiver hacks to try to get the ppm single from it and i cam across this little cord that looks like it can do the job for those people that don't want to take the chance of messing up there receivers.
http://www.mftech.de/catalog/product_info.php?cPath=23&products_id=44
You plug the cords into the receiver and it outputs the ppm signal for you.