Yes, I know. That's precisely what I do. Except I also have a GC-IRE that listens to the IR traffic and sends me the strings via a socket connection. I parse the strings and use them to identify which remote they came from, and use that to trigger a source selection IR message to be sent.
What I did find amusing what that I have several remotes (including the tivo peanut remotes) that appear to have the same IR chipset family. One decoder I wrote will recognize 4 different devices by the first 10 bits or so of the message. They all have the same bit count in each message and the same structure, with the obvious exception that there is an ID bit string at the start and a different way of encoding the button number at the latter half of the message. The tivo remotes also have the last 4 bits being used to indicate the tivo device ID.
An earlier version from a few months ago is here:
http://www.wemm.org/ha/autosource/autosource.c
It is cheap, nasty and a bit fragile, but it works. The GC-IRE isn't too precise. Current versions allow me to detect a couple of harmless key sequences on the tivo remote to trigger exernal scripts that turn lights on/off etc. I can also turn the TV off from a few Insteon KeypadlincV2 buttons in some other rooms.
eg: clear-clear-1-clear on the tivo remote turns off all house lights via insteon. clear-clear-2-clear turns on certain lights. clear-clear-9-clear turns on the garden sprinklers for 10 seconds to water the neighbor's cat if I see her hiding in the bushes and trying to catch birds at our bird feeders. (actually, I ALSO currently turn the bush sprinklers on for 10 seconds every 2 to 20 minutes at totally random intervals to keep the cat on edge)
There are lots of possibilities. Actually, a true universal remote like the Harmony should enable you to program a panel of actions for lighting control etc without having to worry about interfering with a device. I'm just using the tivo peanut remote for this since it is the one that is always around.
Incidently, I really like doing this stuff in such a modular fashion and using unix scripts to glue it all together. Having Unix, X10-RF, Insteon, UPB, X10, IR, rain8net, RCS TR40, ADR2205 etc all working together is a lot of fun. Especially since you can tweak things on the fly without disturbing other things. No reboots etc. My main controller machine has a 14 month uptime right now and that last disruption was to install more serial ports and switch to a different UPS.
This level of hacking isn't for everybody though. It suits me though, and I have as much fun figuring things out as actually using them. This is why Z-Wave is utterly out of the question for me it is a closed system.