I would try to take the receiver apart and see if that increases the range and size. I know the internals of it are considerably smaller.
I'm kinda looking for the same as that little Creative Labs one... except in RF.
I can't seem to find one, though. The RF ones I find are either too big and bulky, or made to work with iPods/Front Row for the Mac.
EDIT: Scratch... I may have found one.
The receiver for the creative remotes really is a lot smaller if you take it apart and wrap up the PCB itself with electrical tape or something - there's a ton of wasted space in the plastic shell. But, it can be made even smaller. I used one in my car for a while a year or two ago and my receiver died on me at one point, so I made my own using a PIC microcontroller.
My board consisted of a surface-mount 8-pin PIC, and a single capacitor. Basically it's a "bump in the cord" when covered with heatshrink. It was used with an external rs232 level shifter because I already had one set up, but I could add that directly to the board instead and it would still be quite a bit smaller than the original board. If there's any interest I might be able to whip up some boards, or get a small run made professionally if there's enough interest.
But don't take it from me! here's a quote from a real, live newbie:
eegeek.netOriginally Posted by Viscouse
then control freak is all u'll need.