There are a number of types of thing which I have designed!
In terms of volume, the foremost type of thing would be websites. This site is one example of such, and I have also done designs for various projects such as the Feedback system for The City and the Dark General website, as well as, in a professional context, sites such as The St. Medan Golf Club.
I have also dabbled in game design. There have been a few projects I've been involved with as a designer so far, but many of them are still ongoing. The only currently completed being Platformer, which cannot really count as a properly designed game. The next most recent has been Dark General, and while it remains uncompleted, you can see things like the Functional Specification and Mechanics Document, in at least semi-complete states (both are living documents, and so won't really be complete until the game is). Finally, there is Badlands, which is currently pending the decision of the Dare to be Digital judges, and has only the most minor amounts of design work put into it so far.
There have been also the comparatively minor tasks of logo and branding design, for these various projects. Professionally, this is not generally something I do, as clients tend to have their own branding already, but I am responsible for the various team/project logos for The City, Dark General, and Badlands.
Finally, there are the various items of Character Design, which are presently on the Art page.