Is there a website dedicated to odd hotels?

Actually, Hostelbookers has a page dedicated just to the Top 15 Quirky and Unusual Hotels Across the Globe. And yes, it includes your 747 hotel ;)

There used to be a blog called Murder Motels. It seems to have disappeared, with the final post from November 2013 and the domain now owned elsewhere. However, you can still browse it through the internet archive. A passage describing the Leland Hotel in Detroit, Michigan, USA:

It’s the stairwell where things get awesome. I’m pretty sure I’ve seen this stairwell somewhere before… maybe DOOM or Resident Evil. Floors 15-10 are relatively okay. Opening the door into the hotel reveals dingy carpeting, peeling paint and odd smells, much like our floor, but the floors are relatively normal looking. By floor ten, the old freight elevator bank is full of trash and the lights are dimmer. Nine and eight are ambiguous — possibly hotel, possibly apartment. Floor seven is where the magic happens. No carpeting, flickering, bare bulbs and doors adorned with personal messages and vague warnings from those who live there. There is a laundry chute, and a strange amount of doors with a photo of an M-16 taped above the peep hole.

Or the Travel Inn in Flint, Michigan, USA:

When deciding to explore Flint, we chose the Travel Inn because of the following negative review:

“They claim to have 24-hour porn, but they DO NOT!!!!”

Even if they didn’t have 24-hour porn, any place that uses non-stop adult entertainment as a selling point is excellent in my book. I called the place up and the lady told me they didn’t take reservations, but they currently had open rooms. “Are you looking or an OVERNIGHT stay?” she asked. Perfect!

If a hotel or hostel is featured on the Murder Motels blog, it's probably an odd one! Plus, chances are that it's very cheap.