If you setup a password for Phoenix BIOS and forgot it, check this
Basically, using the checksum generated (after 3 wrong entered passwords) by BIOS, you can brute-force the pass using a script (provided by the specified blog).
A big thanks to Dogbert.
p.s. it works with a lot more BIOSes than Phoenix.
p.p.s. checked with a Travelmate with locked up BIOS. Password cracked in less than 3 seconds.