I travel with my Titanium often and I'm paranoid about losing it or having it stolen. So I have written three scripts that post my laptop's IP address to the Internet every 15 minutes. I figure if my laptop is stolen, I can use the IP address to help locate it, or at the very least, I can SSH into it and get/remove any sensitive information.
I would like to make this same service available to others using OS X (or any other *nix). I have posted instructions on my keyjoinsoftware.com web site for those interested.
[Editor's note: I haven't tried this hint myself, but it looks relatively benign. You will need to request a (free) ID number from keyjoinsoftware.com to use their FTP servers, but you could also use your own FTP server with some simple modifications to the scripts.
And if this sort of thing interests you, make sure you also read the Phone Home script hint, which discusses another means of getting information from your stolen Mac back to you.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020820012945666