Creating SVG images to use as backdrops

I’ve noticed when I’m looking at websites that have great design a lot of them are using SVG images as backdrops for footers, headers, etc…

The Mainframe site is a good example. Both the large logo on the left side and the colorful blue/red footer image are visually appealing.

How would I go about designing a footer image similar to the one on the site?

Is this something you could create with Gimp?

Gimp (and Photoshop) are raster graphics editor.

SVG are vectors, so you’ll need something like Adobe Illustrator. From AI, you can Save As… SVG or SVGz (compressed format).

Advantages of vector graphics is you can scale them up or down without loss of quality.

I just downloaded Inkscape and I’m playing with it. Do you know of any good online tutorials for Inkscape/web design SVG?