I know all you major bike makers are avid readers, so here is your mission: look at these non-production designer bikes—Christophe Robillard's Victor Bike and Inoda Sveje's Bike 2.0— and spare a thought for "the help", you know, those little folk to whom we pass our bikes to be cleaned after each ride, so they stay looking like the bikes in your ads.
If you know of any more easy-clean bikes, drop me a note. I might make a list. Belt-drive. Rod drive. Lefty forks. Righty frames. Full high clearance mud guards. Oh, and nothing stays cleaner than raw titanium.