Alternative to Adobe Illustrator

Let me know how well Inkscape works for you. Unfortunately, Inkscape does not have everything Illustrator does, but it's still pretty impressive with the amount of tools and functions it provides being free and open source. There are lots of tutorials, examples, and works displayed (which are pretty impressive too) around using it. It's still in active development, so there could be new tools and features in future releases. One of the best things of it being an open source project like this is the collaboration between users and the developers. You get a lot of feedback and support.

http://inkscapers.deviantart.com/
You can click that link and scroll to the bottom for the gallery. It's pretty cool to see all of those images were created from scratch just by using inkscape. Some of them are hard to believe because they look so realistic.