Download VirtualBox from Sun MicroSystems. It allows me to run a win XP virtualization as a regular window. I've been running schwab's professional trading platform through this, and It shares the screen with my 20+ Safari windows with no problem. I can do this because the of version of XP I use only requires 100mbs of ram (you can get this version as a torrent, but make sure you own an original copy of the XP so that it's legit).
Essentially, I have a computer inside of a computer... running WinXP with 283mbs of ram on the virtualization, and I still have 1000mb of ram to do whatever else i want to do.