Inkscape is a graphical front end to an SVG. In some ways it is like Adobe Illustrator but it has a number of extra features which rival Adobe Flash. It doesn't do photos but will trace them and it doesn't do videos but will do animation.

SVG used to be obscure but has been supported by Firefox since version 1.5 and Microsoft Internet Explorer with the Adobe SVG plug-in. It is now a common "bridge" format between graphical applications such as CorelDRAW and Microsoft Visio. It can be converted to a fixed size by programs like "the Gimp" and gThumb without loss, i.e. no jaggies or thin lines. With a little help, it can be converted to and from "wmf" (Windows Metafile) also a vector graphics format.

SVG and Inkscape are free. SVG files are humanly readable (although perhaps not understandable). I have been know to zealously attack an SVG file in pursuit of the "ideal" image.

Every venture needs artwork. Even the graphically impaired but symbolically inclined person can produce simple geometric logos and word art. If you are willing to pay a professional, ask them if they will deliver your artwork in SVG and if they give you a blank stare, save your money.

One fascinating Inkscape compatible SVG is Web 2.0. Come back in a week or so after chasing the links.