The Fourth District Court of Appeal in Santa Ana agreed with a lower court Tuesday when it ruled that a contract written in blood between two Korean businessmen is unenforceable (SF Gate).

Two men at a karaoke bar pricked their fingers and wrote out an oath in blood for one man to repay the other the $170,000 he lost on an investment in his son's company.

So if someone owes you money, getting them to write out a contract in their own blood to pay you back is not the best way to get your money.  I will have to make a note of that.