I've not got any need for this anymore, so it's up for sale. It's a complete package that will allow you to read and clear fault codes, and also enable/disable options that weren't enabled at the factory (audible alarm arming, change the alarm tone etc etc)
It's the kit that's for sale here http://www.ebay.co.uk/itm/BMW-USB-OB...item3f17040409 (for some reason the E46 OBD port isn't fully enabled, so you need to use the pacman connector under the bonnet).
Here's the kit in question (3 discs containing various BMW software, blue OBD cable and black OBD adaptor):
Looking for £25 posted
EDIT - forgot to say, I'm not on here very much anymore, so feel free to email me randomrobb AT aol dot com.