That's basically what I did this weekend with a $20 67mm UV filter for my Nikon D70s.
I was running late for my youngest son's baptism, and was carrying more stuff than I probably should've been (baptismal blanket, camera, tripod, and a bottle of formula in case the man of the hour got hungry), and made the mistake of not putting the camera strap around my neck. When I shifted my loads around to get to my keys and lock my car, the camera strap slipped out of my hands, and CRASH! Down went the camera onto the pavement.
As you might imagine, I thought for sure that the camera was probably trashed, but fortunately, having landed lens down, the aforementioned UV filter bravely sacrificed itself to save the camera.
So I've learned two important lessons:
- Always use at least a UV filter on each lens. Thanks to my filter, I avoided having to replace a kit lens that would probably run me a couple hundred bucks. I had not yet gotten around to getting a filter for my 70-300mm zoom lens, which thankfully was not on the camera, and I'll be remedying that soon along with getting a replacement for the kit 18-70mm lens.
- Always, Always, ALWAYS carry the camera with the strap around my neck. I was lucky this time, but next time, maybe not so much.