UPDATE: Nicu has been posting incremental updates on this tutorial on his blog… to date there are 3 parts in total:
After the last few posts not being actual tutorials, today the inkscape tutorials weblog is getting back into the swing of things with an awesome little howto from nicu.
Nicu demonstrates how to create gears in inkscape, vary them and build them up to create complex “mechanisms”

This weblog is *very* cool- I’m going to have to check this out in detail. Thanks!
This tut doesn’t work as indicated with inkscape portabel, Inkscape 0.46, built Apr 1 2008. With my build I had to do following step:
1.) drawing the cogwheel (as far this step works as mentioned)
2.) you have to mark the cogwheel and Ungroup it. If you omit this step the cogwheel is no path
3.) draw some spokes, center and Unite them
4.) draw a circle with a diameter less then the one of the cogwheel and put the spokes centred ON top of it and build the Difference
5.) center the result from step 4 with the cogwheel and build the Difference
6.) draw another smaller circle and center and Unite it with the result from step 5
7) draw another smaller circle center it with the result from step 6 and build the Difference
Thanks for council, I will try to apply at myself.
I have one but maybe it is ugly:
http://desaininkscape.wordpress.com/2012/05/08/tutorial-inkscape-gerigi/