If you are looking for new horizons in your diving sphere, this may be an opportunity for you.
Deep Ocean Expeditions offers trips in submersible to below 800 feet in various famous world locations. An expedition to visit the RMS Titanic has been organised for July 2005, and more details are available here.
Previous dive expeditions include shipwrecks of the Mediterranean, the Azores Undersea Volcanos, the Pacific Hydrothermal Vents and many others.