Personally, I would first use it for entertainment in odd ways to die (autoerotic exfictiation, choking on a cupcake) then I'd use it for personal gain. And if by the time I had no more personal things to do with it, I would use it the way Light did. The complete truth!!!

Hmmm...
First I would use it for revenge. Then, I think I would save it for protection, if someone had me at gun point...they'd be written down. XD