The Everdream corporation (http://www.everdream.com) has released a

service which will encrypt or delete files on a laptop or PC if stolen. 

The software runs as an agent on the computer–this connects to the

control centre of Everdream which extracts network location details from

the computer and if the computer is stolen will either encrypt or delete

files specified by the customer.  A policy is created by the customer to

decide whether encryption or deletion would take place, and which files

are targeted.

The service costs around $6 per PC.

The usefulness of such a system is debatable, it assumes that the thief

is stupid enough to connect to the internet.  Most stolen computers will

be reformatted as soon as they are switched on; windows logon  passwords

will prompt this.  If the computer was stolen for the information

contained on the hard disk, it’s unlikely that it would be connected to

the internet before all of the desired information has been pulled off.