TUAW Tip: hold ctrl-cmd-d while mousing for live definitions

Many of you power users know that pressing ctrl-cmd-d in many Mac OS X 10.4 Tiger applications (except Firefox and a few others) will yield a handy pop-up definition window, drawing information from the standalone Dictionary app that sits in your Applications folder. However, if you didn't know that, well, you now have at least one reason to claim the 'power user' (nerd!) throne.

I just found that if you hold down that keyboard combo, you can move the mouse over text to receive a live pop-up that keeps updating definitions as you mouse over new words. It seems to perform pretty well, though I am running on a fairly recent 1.83 Core Duo MacBook with 1GB RAM, so YMMV.

I'm not entirely sure how handy this will be in daily activities, but I figured I'd post it since you creative readers so often surprise us with finding new uses for tips like this. Enjoy.