[jdietrich]

I have a large scar on my calf from a conventional chainring. If your chain is on the inner ring, your crankset is basically a blunt circular saw.

[jacquesm]

Ouch. I very narrowly escaped that (but did break my leg :( ). On intermediary 'sports' bikes and mountain there typically is a guard ring mounted on the outer gear ring to mitigate some of that risk. Most road bikes don't have them though.