Now that a US greenback is worth about the same as a Zimbabwean dollar, the new global currency is likely to be laptops.

They're lightweight, high value and easily stolen from coffee shops while you nip up to the counter for a refill of your cinnamon and basil iced frothaccino.

But here's a bit of clever open source software available that could help you track down a stolen laptop without even getting your magnifying glass and deerstalker out.

University of Washington researchers have created Adeona, free IP (internet protocol) tracking software that occasionally sends its current IP address and related information to OpenDHT, a free online storage network. This information can be used to establish the computer's general location.

Silent mugshot

When running on a MacBook, Adeona will also use the on-board webcam to surreptitiously send a photo of the dastardly thief to the same server. You can then log on using a safely encrypted password and collect the data to hand over to law enforcement authorities.

This is the weak link in the chain, obviously. Chances are that your local police force will 1) not have the foggiest what you're talking about, 2) not believe it even if they do understand, and 3) lack the manpower to do anything about it even if they wanted to.

Try it for yourself by downloading Adeona (named after the Roman goddess who returned lost kids) at http://adeona.cs.washington.edu/.