Sam Raimi doesn't have to work on anything at all if he doesn't want to, but his options are wide open. Following the success of his Spider-Man films the red carpet now belongs to him. He's kicking back and pondering quite a few projects right now, including the possibility of Spider-Man 4. From the sound of it, he (and Marvel and the studio) realize that they need to do something very different with the next Spider-Man film considering the reaction of moviegoers to the weirdness that was Spider-Man 3.
Regarding Spidey, Raimi stated:
"Right now, Sony is meeting with different writers to try and bring a fresh, new story and approach to the 'Spider-Man' franchise, different writers have been coming in and spinning different tales of where 'Spider-Man' could go from here... A lot of people are working very hard to work on a really good story right now."
He's not contractually obligated to direct, but if the right story and circumstances arise he's open to it.
Regarding other movie projects, Raimi said that he's still open to the idea of having someone come in and do a remake of the cult classic Evil Dead. The original was done on a shoestring budget and shot on 16MM and he says he'd love to see "a young filmmaker to reimagine and remake it at some point." But before you get all excited (or angry) about it, at this point it's all just talk.
And in case you've forgotten, Raimi is also the guy behind the American Grudge remakes of the original Japanese horror films. There's a Grudge 3 in the script stage at the moment and they're trying to get it done before the possible strike next year.
What else? How about a remake of 20,000 Leagues Under the Sea? This is the first I've heard about this project and he's producing the film. Regarding a movie based on The Hobbit, Raimi says he'd love to do it but thinks that Peter Jackson (who directed the Lord of the Rings trilogy) should be the man.
Finally, in an interesting counterpoint to the fact that he laments that Evil Dead was made for such a low budget, he has a film in mind that seems to be a throwback to that one called Drag Me to Hell. It's barely into pre-production and all he says about it story-wise is "It’s the story of a curse. Real bad things happen." It will be directed by Jeff Lynch, who did the second unit work on the Spider-Man movies.
Sam just finished up producing the upcoming vampire flick 30 Days of Night which opens this Friday.
The man is not hurting for work. :-)
Sources: Sci Fi Wire and MTV Movies