Like The Los Angeles BB Murder Cases, L Change the WorLd is a novel rather than a manga, but unlike it's predecessor this book takes place after the Death Note series.
Once again, I don't want to give too much away, but I will recommend it to any avid Death Note fan (I'm looking at you Stocky

I gave it Four and a half Flaming Croissants of Doom out of Five.
P.S. Someday, when I have more spare time than is good for me, I shall create little flaming croissant animated gifs to add to these reviews. Someday