A BBC travel feature lists a few underwater oddities, such as this bedroom in the Maldives. A little pricey, you say?
The most luxurious underwater room option transforms the Ithaa underwater restaurant in the Maldives into a private bedroom ($11,710 per night), including a private champagne dinner and breakfast in bed. The resort needs 14 days advance notice to book it as a suite.
Assuming money was no object, there is no way I would be able to sleep with that water overhead. With my luck, the water pressure would cause a collapse of the protective shield.
Toronto has something like this at one of their museums; to go from one room to another, one has to travel through this tunnel-like affair with the surrounding water, just like pictured above. It took me awhile before proceeding.