Free Vector Graphics Adobe Illustrator Alternative

The name: Inkscape
The site: http://inkscape.org/

What it does: Allows you to make advanced vector graphics. In case you don't know what vector graphics are. They're basically (theoretically infinitely?) scalable images. Generally, they look kind of cartoonish, but still serve a great number of purposes. I believe the reason entertaining videos and animations are done so fluidly in flash is by using vector graphics.

Is it free: Of course. Free download.
What operating systems does it run on currently? Check here to be up to date.

Sample work that I did:



If you're ever searching for a tool that you're used to in Adobe Illustrator and aren't sure what it's called in Inkscape, make before to check out the Inkscape wiki, especially the AdobeToolMap page.