I did a post about building a pool with a glass bottom featuring Dara Torres in a very sloppy Photoshop rendition. I concluded that this would be the best way to observe a swimming race since all of the work takes place underwater. Here is another pool found on OOBject.com that I would pay "mad bank" to swim in. Put a video camera on a tripod and then see any and all mistakes you ever make when you swim across a pool. [Link]
I might swim in this pool and have somebody film me.