There is a full thread going on here about choices of scanners / scan software:
http://www.xoutpost.com/bmw-sav-foru...ml#post1023577
I seem to be one of the few who like AutoEnginuity software. It comes with full support and updates from the developers.
Many of the other choices are open-source or cloned software with no support. The most capable is the BMW INPA/DIS that you can find on eBay. This is the same software the dealer has. No support except the various forums. Most people dedicate a laptop just to this since the requirements are slightly out of date (Win XP I think) and it is of questionable provenance. BMW Scanner 1.4 is another software package that is also very popular and can be found online around $60 I think. Either of these two software packages require you to find a compatible cable / interface to fit your car (or you may buy it bundled).