I would like to upgrade the bios, for instance, I would like more accurate temperature and fan speed readings. However upgrading the bios is dangerous since, if anything goes wrong during the process the computer will not work and until a new BIOS chip is ordered and installed. There are a lot of reports on the Sudhian newsgroup about problems during bios updates and a lot of people there suggest using the Bios Savior.
The Bios Savior model number required for Shuttle SN25P is : RD1 PMC4
I got it from here because I'm in the UK and because they also had some sata cables that I needed. It can also be bought from here