Carramell Dansen, definatly.
And one thing that annoys me are those death note ones where the person cosplaying L constantly accuses The person cosplaying Light/the audience/himself/anything that moves of being kira for no apparent reason, eg. "You just breathed, therefore there's a 46.04683735% chance that you're Kira!". Usually followed by either a dance routine or L chasing Light around screeching "KIIIRRRRAAAA!!!".
Thank god the death note cosplays have gone down a little. I like the show, but messing up your hair or wig and putting on jeans and a t-shirt is just a cop-out when it comes to cosplay.