A few months ago Michelle shared this great tutorial on plumbing pipe shelves for her bathroom. Over at IKEA Hackers I spotted this unit that also uses plumbing fixtures but pairs them with IKEA products instead.
Ikea Hackers provides some basics:
Description: Floating bathroom shelves from Kee Klamp fittings and Lack shelves. Kee Klamp fittings look like a great alternative to Stolmen posts, especially if you don't want post that go all the way to the ceiling.
Need more help? check it out over at Simplified Building.
(Images: Ikea Hacker)