I've had a huntsman run up my leg very agressively before, when I uncovered it under a rock while gardening. It's pretty funny as the first reaction is to leap about shouting all sorts of things, before the brain kicks in and let's you know that it was a spider.

I have been bitten by something before (never worked out what) that progressed from itching lump on my leg, to full on swollen face, legs, feet, arms and hands, skin burning bright red, intense itching, added a few kilos of fluid to my weight within 24 hrs, heart rate up around 120 while at rest... scary stuff. They put me on steroids etc, and it went away after about 4 days. Not a fun experience, and no idea what bit me.

After the recent huntsman experience, I'm checking inside my gloves before putting them on now.