Photocopy and scan your key identity documents eg Birth Certificate passport or drivers licence. I upload a copy to the cloud to my dropbox (a free service that allows me to store photos and documents). You can use Google docs for the same purpose.
You can also send it as an attachment in an email to yourself or your travelling companions.
That way if everything you own is lost or stolen, your documentation is always available. (as long as you remember your password!). Make sure you log out of your email or dropbox when you finish at a public computer. You don’t want someone else accessing your files!
These services are also useful to upload photos on the run. If you get some free wifi on your hotel room, upload your pics. This means you have less chance of losing those valuable pictures if your phone, camera or memory card are lost or stolen.