Its important to know that its very common for the DSLR's sensor to get dirty as well. I spent a year a year thinking my expensive 20D was ruined because no matter how much I cleaned the lenses, spots would show in the picture. It turns out it was just the sensor that needed a cleaning.

I tried using think and backdrop, and found what I really needed was a virtual desktop rather than an isolator. I'm a java web developer, and what's worked best for me is to have a work environment desktop (IDE, terminal, browser) and an "everthing else" desktop (email, itunes, rss reader, etc). Keeps things simple…