There are app compat VM's with XP and IE6 for a variety of VM platforms here: http://modern.ie/en-us/virtualization-tools#downloads

There's also XP Mode for Windows 7, although I don't know how secure or supported that is: http://windows.microsoft.com/en-us/windows7/install-and-use-...

There's also Enterprise Mode in the IE11 (Windows 7 and 8) that makes it easier to get legacy web apps working in IE11: http://technet.microsoft.com/library/dn640687.aspx