Suito Homu Remake...
That would kick ass. Imagine; it would have to be free, and available for all online. A completely 3D makeover, and a revamped combat system. I'm thinking along the lines of KOTOR-style turn based combat. Sure, would be problems with renovating it, but it would still be incredible if pulled off correctly. I just wish I was a programmer...
Note: Of course, the house floorplan would be exactly like the NES', there would have to be the same enemies, and the music would have to essentially be the same. It would be an homage, not a replacement.
I actually thought about making a film remake of the game itself. cuz there's a real creepy, decrepit mansion down the road from my school.
EvilNES!! Make it, you know all your NES buddies want to see it