The Mansion on "O" Street in Washington DC is not your usual DC Hotel. In fact it is a quirky place full of secret passageways, rooms filled to the brim with memorablia (and junk) that is the perfect place to hide from the public. If you can find your room after opening a full length mirror or bookcase you might be lucky and remember how to get back to the lobby area.
If you are looking for something a bit different to do in DC then you might want to see if you can find one of the 32 hidden passageways that lead to the 100 rooms. I don't think I found half of them while I was there and trust me I tried!