it's tagged windows

Run IE6, IE7, and IE8 on the Same Machine Using Windows 7 XP Mode [HTML & XHTML Tutorials]

XP Mode is the only reason I bought Windows 7 Professional. For web developers, it removes the barrier to regular IE testing, saves countless hours of waiting for VMs to start, and allows you to spot rendering problems early. It’s impressive and certainly makes the extra cost worthwhile. However, be careful to choose the right version.

http://articles.sitepoint.com/article/ie6-ie7-...