Hmm, let me think. I don’t want to go get my Mac and look, so I’ll do this from memory.
The calculator, clock, conversion chart, and calendar. Sing That iTune, an iTunes status widget, and an iTunes album art lookup widget. A periodic table and a Chemfinder.com lookup widget. And a SI newsfeed and a widget that works with XM Radio online.
I think that’s it.
I’ve got iStat, Dictionary, Weather, Calculator, Calendar, two clocks (one set for central time, the other for London), and thanks to this thread, Sol and TV Forecast.
It’s not a widget, but some of you might like Dasher. It’s a preference panel that turns the Dashboard on after the computer is idle for a few minutes. For one thing, it’s just nice to see all that data when I return to my computer. It also means that Dashboard widgets are already in memory - so I don’t have to sit and wait for them to load up and then update.