I have to go with the angle grinder too. Eye protection is a must, and also
well fitting gloves that come up the arm like gauntlets. I've had slivers of
metal stuck in my wrists befor that were ejected by the grinder. I seem to
recall from my high school shop days that statistically, the jointer was the
tool most likely to cause serious injury.
Of course the usual all apply. Don't wear loose clothes or ties, make sure
you are well rested, and be sure you know how to operate the tool. I'm sure
more injuries are caused by misuse and carelessness than by a defective or
For me, on some tools, the best thing you can do is be sure you are in a
comfortable position while using the tool. You're more likely to hurt
yourself if you're in a bind to begin with.