Check out the rugged Panasonic lenses in the photo above. No, Panasonic didn't quietly release ruggedized versions of the 100-300mm and 42.5mm that you didn't hear about. The lenses were upgraded do-it-yourself-style by photographer Nate Cowlishaw at home using rubberized undercoating designed for the undercarriages of cars.
Most lenses nowadays come with a multipurpose chemical coating, meant to not only protect the lens a bit more from accidental scratches, but to also reduce reflections and aberrations and provide a clearer image. How the coating actually works might be a mystery to many of us though.
Do you ever clean the front element of your lens by fogging it up with your breath and then wiping it off with a cloth? If so, you might want to stop -- Nikon says the practice could be damaging to your glass. Apparently human breath contains stuff that isn't too friendly toward camera lenses.
Ross Technology Corp. has developed an amazing silicon-based spray-on coating called NeverWet that can make almost anything completely waterproof. An iPhone sprayed with NeverWet still functions perfectly after being submerged underwater for half an hour. Spraying the coating on clothes causes liquids (e.g. water, oil, chocolate syrup) to slide right off.