I did L on a whim at Otakon 2004 - the costume was ridiculously simple, just some black hairspray and a white shirt - and it was very fun. Misa was also done on a whim - I mostly cosplay boys, or male-ish characters, so to do the sexy Misamisa would be a rare treat. And in mid-July, my hair grew out long enough for me to pull off Light Yagami.

All three of the costumes are purely purchased.

Katsucon

Anime Central 2005

Otakon 2004