Instead of re-inventing the wheel, here is a link to an excellent post on how to get to the memory slots in an Asus EeeBox PC:
A while back we had picked up a set of plastic pry tools for our iMac as we were intending to get into the case to have a look around along with upgrading what components we could. They would be perfect for this task if we could find them! :(
We ended up using a pair of PC case slot covers with straight ends to do the prying after first using a finger nail to pull the end away from the cover. We will try and dig up the Apple tools or pick up another set online as they would be the perfect fit to get things started.
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book