IE7: User Agent String Utility Tool V.2
I *LOVE* this app. It is a *very* cool utility that opens an Internet Explorer 7.0 window which is configured to report its identity to websites as being Internet Explorer 6.0 - an excellent way to work with Web sites that are improperly coded to only recognise IE6 and earlier.
http://www.microsoft.com/downloads/details.aspx?FamilyID=9517db9c-3c0d-47fe-bd04-fad82a9aac9f&DisplayLang=en
This is much easier than messing around with the registry, and most importantly, other instances of Internet Explorer 7 will not be affected. It makes testing Web sites so very much easier.