When I noticed a movie on the horizon was named Slither, I thought at first of an old paperback horror thriller by John Halkin. The American edition featured green snakelike creatures making their way up through a drain. Apparently there are two sequels I didn't notice on the racks.
The film seems to be an original from James Gunn of the new Dawn of the Dead and live action Scooby Doo flicks.
Gunn is great at blending humor and horror, and the trailer suggests Slither might be one of those winning mixes of gross-out horror and laughs.
It stars Nathan Fillion of Serenity and Firefly, and a cast of a lot of slugs.
View it here.