The Dionaea House
When you have the time, sit down and read this, all of it, and follow any links you find when you get to them (don't save them for later). It all weaves into a great and spooky story. Sounds like something I'd do in Kult mixed with House of Leaves.
Now, once you've read this, note that I read it last night, about 1 in the morning, all the lights in the house are off, and afterwards shut down my machine and had to head upstairs, in the dark, to my dark second floor bedroom, where Dianna was asleep and thus there were small sounds in there. Yeah, über-creep factor times 10.
Side note: apparently, the author is involved in making a movie based on this, but it seems to have stalled.