Hey, I've found something, but I have no idea how to impelemnt it, as I have the coding knowledge of an amoeba on crack.
The details are all on the website, but it could allow a Sony Errikson phone to become a 'follow me' remote for HA, Media control, and pretty much everything else. It may, of cours be already implemented, or this cannot be used for whatever reason, but, hey-ho, here it is:
http://www.laser.com/dante/irman/irremote.htm