JR,Futaba,Smartfly all make "matchbox" devices. JR also makes a Channel Expander that allows using one channel to control multiple actions from one switch. Smartfly,Powerbox,Emcotec,etc. offer servo expander devices. These are in addition to the products already mentioned. There was a thread on RCU about somebody using a Spektrum 7 channel radio and was able to fly a very complex jet by utilizing the 7 channels plus a combination of some of these other devices.