I would have a hard time objecting to becoming the owner of this bathroom:

Photo Credit: Sunset

Or this one:

Both are exquisite bathrooms, but the windows are maybe my favorite part.  I started thinking about this practically though, and who honestly has a private enough home that you could pull off those kinds of windows in the bathroom with out shocking the neighbors?  Especially if you live in an urban area, it would be quite a challenge. 

Unless you want to get a little bit creative:

While I’m not a huge fan of frosted glass, I think it can be excused in the bathroom.  Especially if you pair it with clear glass, you could get virtually the same effect while maintaining your privacy.  In my mind you can never have enough natural light in a space, so anything you can do to get it there is acceptable. 

You could also get a similar effect using some lattice.  Either transplant established plants onto your lattice piece, or grow some specifically for the job, and place them strategically outside your bathroom windows.  I like this approach especially because it has the potential to make your bathroom feel like a lush, leafy hideaway.