One of the worst problems a developer can have while developing a web application is to make it compatible to the maximum browsers possible.
If you are running Linux and don’t have Microsoft Windows installed, or you have it but you don’t want to switch to it just for testing your application in Internet Explorer.
Happily you can use IEs4Linux to test your application, currently supported versions are 5, 5.5, 6 and 7 (beta).
You may read the installation instructions here.
An alternative to this is, if you have Microsoft Windows installed, it’s partition mounted and wine installed you may run the Internet Explorer that you have installed there.