Anything hydraulic. I think hydraulics are absolutely wondeful, but highly unforgiving. A few years ago a friend of mine cut 4 fingers off. He got them back, but they were about an inch shorter...
And routers scare the h*ll out of me to. One of the only tools that doesnt have a reverse thread holding it on. Saws are designed to be put on finger tight and when operated, spins the nut tighter, not routers...
