How many different web browser/platform/versions can you debug in simultaneously on one screen? With Mac OS X, and two windows virtual machines I can have 11 different browsers open at the same time and cover about 99.5% of desktop web browsers users;

• Firefox 3 for Mac & Windows
• Firefox 2 for Windows
• Navigator 9 (Firefox 2 equivalent) for Mac
• Internet Explorer 6
• Internet Explorer 7
• Safari 3 for Mac & Windows
• Opera 9 (Mac)
• Google Chrome (Windows)
• Lynx (terminal)