You mention of use only on laptops for the power button trick...but this is not so!

Older mac keyboards will have the power key as well, which works the same.
Those macs which don't have this key (bad Apple!), can pretend they do by hitting control-eject on the keyboard for the same effect. I use this on my various different G4 towers all the time, as well as other systems in labs I've worked at.

Once the dialog box is up, you can simply hit "s" to sleep, "r" to restart, Escape to cancel, or Enter/Return to shut down. No mousing around needed.

Wow, I can't believe Salling Clicker wasn't mentioned here. When I physically walk away from my desk with my phone in my pocket, my computer locks - no touching required.

I tried this hack about a million different times, and it absolutely won't work. I even can see my set keyboard shortcut in the Keychain toolbar item menu, and I still have use the menu - doing ^F8 doesn't seem to do anything on its own, although it's supposed to bring focus to the toolbar.

I'm running a 300MHz G3 iBook, so I'd rather not have to install extra software - I need all the processing speed and RAM I can get for other things!

Thanks in advance, and sorry for bumping the thread!