I just cut the fuck out of my head and i got a cromson mask going at the moment and it won't stop... i am about to put a turnicate on my head because this is so annoying.
They react chemically with the blood and basically burn the wound shut. Hurts like a motherfucker, but quite effective. Not pretty either...you usually have what amounts to a burn mark which lasts a for a few days.
Surgeons use a medical grade superglue all the time and god knows most of the folks on this site don't give a rat's behind about "medical" grade anything. The reason that I know about the superglue thing is that I used to own a meat packing plant and all the meat cutters carried a tube of superglue. Just clean with antiseptic first and glue it shut, end of problem. It is great for papercuts!