TomTom is one of those companies that I both love & hate.
I have fond memories using their mapping on Psion (5 & netBook) and later on an iPAQ, with a collection of serial, CF card & Bluetooth GPS receivers. I still have all of them, gathering dust.
Then of course they entered the market with their own integrated hardware; and dropped support for the software product almost overnight. And, yes I do have a TT SatNav! :)
Then again there is their irritating habit of disabling obvious features and actively preventing workarounds with firmware updates.
Rant over ... time for a beer. =>