Last summer I had an experience similar to Gus'. I noticed a couple of little raised marks on the back of my right hand, about a half mm apart. I hadn't felt anything prior to that, and the marks didn't hurt. I scratched them, still didn't feel anything, forgot about it. Within the next week, I had an oozing sore the size of a half-dollar that needed constant drainage (think of slimy yellow custard), but didn't hurt at all. I was at a conference stock full of MDs. but they were specialists in another discipline. I got a script for a broad-spectrum antibiotic, and sterilized the hell out of it every few hours. I decided that if it did not start to heal within a few days, i would go to the hospital, but after another week, it did start to heal, and I am left with a faint brown discoloration the size of a nickel on the back of my hand. Eventually I spoke to a pro friend about it and he said that I had perfectly described a recluse bite, and that I was a farkin idjit for not seeing a doc who knows about these things.