Here are some light novels I've read recently:
Devil's Cape by Rob Rodgers - Devil's Cape is a modern superhero novel set in the fictional city of Devil's Cape, Louisiana. The world it is set in is one in which superheroes and villains are a fact of life, and the story focuses upon the origins of three heroes and their inevitable team-up. Rodgers does a great job of bringing the city of Devil's Cape to life. Devil's Cape is the fictional sister-city to New Orleans, and I was a bit afraid, as someone who loves New Orleans, that Devil's Cape would be end up as a caricature. Not so. Yes, the city is over-the-top in some ways, but these ways mostly make sense given its history.
The three heroes Rodgers focuses upon have a broad range of origins (mythological, magical, and technological). At least one of them was based upon a character he created for a RPG. Moreover, the book was published by WotC. As such, you'd think it would be ripe for pillaging for RPG inspiration. You'd be right. The tone in Devil's Cape is a great one for RPGs - it manages to be a fairly dark and brutal world in which death is a very real possibility for heroes while not taking itself too seriously.
Keeping It Real by Justina Robson - This and its sequel are cyberpunk-fantasies set in a Shadowrun-like world. Earth sort of ran into some parallel dimensions (wherein dwell elves, demons, faeries, etc) due to a quantum accident. The main character is a protoype cyborg operative who is presumed dead by all but her employer. You know the type. Yes, she ends up sleeping with a bunch of non-human things. It is one of those books. That said, it wasn't bad... and by the end of the second book, there are a bunch of rather unique characters who have pulled together into a team. It looks a lot like many a very diverse group of PCs I've seen.
Mind the Gap by Christopher Golden and Tim Lebbon - A modern dark fantasy set in London, this is not the Neverwhere knock-off I expected it to be. Yes, it features a magical London (sort of) and people living in the London underground. No these people aren't really supernatural (except for one or two... a little bit). Apparently, this is part of a series, but I'm not sure what the connection between the books will be - I suspect just thematic. We'll see. Anyway, I enjoyed the book. I don't know that it had a lot of RPG applications, but that wasn't why I was reading it. That said, I've enjoyed everything that I've read by Christopher Golden. If you haven't read The Myth Hunters, you should do so. Now.