On the prowl for another AUX unit following my wreck... This is tempting me since I've got a better job than when I got my first TSX...Check this thread out.
http://www.tsxclub.com/forums/1st-gen-electronics/61339-intergrated-bluetooth-aux-04-05-a.html
The GROM unit and the USA spec are popular choices for AUX adapters, and they do more than your usual AUX cable, allowing you to use your steering wheel to pick music and adjust the volume. The GROM unit also has a bluetooth package since the 04-05 doesn't come with bluetooth.