I watched the Avengers and Percy Jackson and the Lightening Thief with my cousin last night and I was hit by inspiration. To be fair, I only read the Lightening Thief out of the Percy Jackson and the Olympian series, but I did read a lot of fanfiction, so I was thinking, what if Sally Jackson was actually Loki? That makes Percy a god, not a demi-god. Unless Loki turned himself mortal while living as Sally, but that's no fun. I want Percy to know Sally is Loki, but for his own sake, he knows the theory behind magic but has never actually used it lest he draw Asgardian attention to himself. So Avengers PJO crossover anyone? Where Loki comes back to himself because he sees Percy knocked out by debris and a Chitauri about to kill his baby boy and immediately goes MamaBear on everyone who looks at Percy wrong.
Percy will be all, "Aww, mom! Stop! I'm a big boy!"
And Thor will be a giant labrador puppy.
Fun? Yes? Fun.