This has been listed before and the price tends to be just under £50 + del. I've been looking to get a cheap 2nd satnav so have been keeping an eye on it and noticed today it is down to £43.49 including free delivery.
It comes with turbodog software (which some people like, but not many) but can be changed to use other software such as tomtom. I've bought this unit previously and it is a great little unit. My father-in-law was very sceptical about it after using tomtoms for years but is well pleased with it.
It can also be used to play mp3 and mp4 files and comes with a 2gb sd card - which can be upgraded to 4gb.
The instructions to change software are very simple and links can be found in the ebuyer reviews.