I just paid £1.95 at this site:

http://www.m-99.co.uk/Mobile_Phone_Unlocki...orange_spv.html

For what was described as:
"A PD download to unlock the Orange SPV C500 and C550 in seconds. All that is required is the original USB cable that came with the phone and ActiveSync (Free for download from Microsoft.com).

Your download link will be available INSTANTLY following your order being placed (via a download link). The software is fully compatible with Windows 95 / 98 / ME / 2000 / XP and XP Pro."

Surprise surprise, it turned out to be a link to this excellend forum! I wish I'd just donated the money to you guys, do you have any connection with that site?
If not, should I ask for a refund?