There are endless websites with suggestions on how to improve or completely re-do your bathroom. It all comes down to two basics: your personal tastes and costs. I found a nice collection of bathroom remodeling ideas, with photos (a necessity), at http://www.abathroomguide.com/.
I love the shower tile that can be a work of art in itself. The addition of clear glass shower doors provides a look of luxury and shows off the beautiful tile pattern.
The shower heads can be almost anything you can imagine.