I'm rather busy today, so without much ado, here are my
Changes that I mailed the original author:
touch the code here and there to get it to compile (gcc4.3.1, linux)
clicking in centre can be configured to select nearest icon, do nothing, or close the menu
can be configured to obey Fitts' Law (extending the pie-slices infinitely, or at least to the edge of the screen)
can be configured to ignore NumLock; otherwise, triggers that have modifiers are no longer recognized when NumLock is enabled
triggers take modifiers of the form Mod4 as well as Hyper, Alt, etc. The mapping is determined at runtime, per display.
the menu can show sticky icons only (Launchers, the benefit is that the menu is always the same size and can thus be operated by rote / muscle memory), running applications only (WindowList), or both (Mixed, this of course is the original mode). Different triggers can open different views.
new button action toggle: switch from Launchers menu to WindowList and vice versa.
new directive key. Like button. Keys that are available when the menu is open. Same actions available.
spin-step can be configured (my mouse-wheel is slowish). negative step reverses rotation (my wheel seems to be configured opposite to Markus').
el cheapo user-install target added to Makefile. Use at your peril.
new sample-rc added to illustrate the new options (binary defaults to original behaviour). This is what I use: right click opens Launchers menu, then right click toggles between that and WindowList — I like to keep them separate. Clicking in the middle closes the menu; the menu obeys Fitts' for faster operation. Specifically this means that the menu behaves pretty much exactly the same way the one I use in Firefox does.
finally, the icon zoom can be disabled; this annoyed me no end at first; now that I can actually disable it, I actually rather like it. Duh.
Possible future extensions:
Show the application-name and/or window title of the focused icon.
In window-list, get icon-resource of running programs that we don't have a dedicated icon for.
Get rid of the pseudo-transparency!
So. You can now configure PieDock to wait for some key or button (Shift Button3 or Shift Menu in my case), usually with some esoteric modifier so the usual keys are still available to your applications, or you can configure you window manager to open PieDock if the desktop (or rather, root window) is clicked in an appropriate manner. I'm using compiz/fusion, which makes the forthcoming desktopclick plugin the relevant solution. Build, install, configure, done.