Compatibility testing for older versions of Internet Explorer can be a nuisance, and doubly so if you're on a non-Windows platform. Handily, Microsoft provides free virtual machine (VM) images of Windows running specific IE versions that you can use in your hypervisor of choice, and the recent addition of IE 11 to the set seems a good reason to revisit that option.
The images, which cover all versions from IE6 through to IE11, are valid for 90 days, after which they automatically expire. Windows users can access images via HyperV, Virtual PC, VirtualBox and VMware Player; Mac developers have a choice of Parallels, VirtualBox or VMware Fusion; Linux users can only use VirtualBox. There are some limitations on the VM images designed to stop people treating them as a free source of Windows licences, but for browser testing purposes they're a handy option.