Got inspired to make another remote control, only 5 buttons this time (vs 12 or 16) and to go in a nice case:http://www.polycase.com/fb-45-serieshttp://www.polycase.com/uploads/41361315577904.PDF
page 5 is the board drawing of what fits.
So here's my version of the card, and the schematic.
Plug in a small LiPo battery, http://www.tenergy.com/Tenergy-Lithium-Ion-Polymer-3-7V-240mAh-062025-Rechargeable-Battery
and an inexpensive RF transmitter.http://www.robotshop.com/433mhz-high-sensitivity-transmitter-receiver-pair-rxa30.html
Was thinking USB microB for power from USB port to charge the battery, wil have to see how diffcult it is to pop open & access the connector.
Requested a sample case, will do some playing with cardboard mockup of the card & see how things fit.
Looks like the battery under the buttons and either RF module under the uF would - will come down to height I think.
Drawing says 0.206" is available - which is 5.2mm?
Might have to keep looking!
Hmm - maybe go to 0.8mm thick PCB (vs 1.6mm), make it sit up off the base some & get 6mm underneath?