So, you're either lucky enough to be able to buy a SolidWorks license outright, a student with a dream, or like me and provided with one by your employer. Too bad you're a Linux user too, right? Wrong! Once you have SolidWorks, running it in Linux might seem impossible. That's technically true, but there is a workaround that I'd like to share with you.
Let's assume for a moment that you have at least one machine that you bought which originally had Windows on it. If you're like me, you have a couple of these. Unfortunately they don't usually come with installation disks from the manufacturer nowadays; but their license keys are still valid if you can get a hold of some! (The disks are generally available through various legal and hazy means, but don't worry! If you have a disk and install Windows with your license number, it's a fully legitimate installation and you won't be bothered.) Now that you have those disks in hand, install Windows onto a VirtualBox guest machine. If you're running Vista like me, allocating 2GB of RAM to the VM will let you run SolidWorks with no problem; but keep in mind that exceeding 50% of your system memory is generally a poor idea.
Once you have Windows installed, install SolidWorks in the VM.
Now, we have a virtual machine running Windows and SolidWorks. Big deal, right? Anyone could have told you to do that. In order to run SolidWorks in a manner befitting a true "First Class Citizen" of your desktop and have a somewhat normal workflow, you need it to be seamlessly integrated into your Linux desktop. Lucky for you, VirtualBox has a "seamless" mode that you can enable! Press Host+L to get to it, and voila! You're running SolidWorks on Linux.