Nico Westerdale's "Dirty Fingerprints" reminds us of the layers of use our work computers endure. Take a look at your own monitor, under that lovely glare of your office's fluorescent overhead lights and witness the grey leftover fingerprint marks on the screen, your own, as well as those of colleagues who've touched your workstation. Westerdale's piece is screensaver that gathers mouse-clicks as your monitor (keyboard) gathers fingerprints. The program visualizes the clicks (on collaborating websites) as dirty fingerprints on the user's screen. After five minutes have passed, the program checks to see if a new fingerprint has been placed. Clicking on a collaborative site isn't the only way to interact. You too can add to the network of sites by offering a simple line of code to one of your webpages--without a trace to your own web site's visitors. Note to Mac users: this screensaver is currently only available for PCs running Windows.