from the bag thread:

LowePro TopLoad Zoom AW
~$39.90 @ B&H

This is the bag I use whenever I ski with my camera. It has a chest holster so it sits right in front of me all day. It's a bit awkward at first, but once you get used to having it there, it's awesome. It's like a workbench for your camera and it makes lens changes very easy. The bag comes in many different sizes, I own the biggest size they make. They've changed the name on this a few times, so just look them up at LowePro.com and get the size that fits what you need.

This bag will hold a 1 series camera at the top, and it's tall (deep) enough for a 70-200mm f2.8 attached. I can also fit a 12~24mm & (sigma) 24~70mm f2.8 stacked in there. I haven't used it yet with my newer lenses (I will Saturday) so I'll report back on other combinations that work. There is a small pocket in the front that will fit a flash, or a lens if needed, but there is no padding for it. There is also a AW cover that covers the entire bag the way you see it there. It leaves what's touching your chest uncovered.

I've skied 100+ days with this bag and I've had no problems with any water/moisture. It also comes with a shoulder strap if you want to use it as a normal bag. I don't do that because it's not stable when you set it down. For me it's a chest pack, and nothing else. You can also get creative with the straps and attach this to a backpacks straps... So you can hook this to the backpack's straps similar to the sternum strap (but much bigger). It makes for a good way to carry your photo gear so it's accessible. The other plus with this is it gets your ~10lbs of camera gear in front of you, so it balances the load. In that shot, I had 40 total lbs of gear, 30 in back, 10 in front. I put the camera bag on first with it's harness, then the pack over it (the camera bag's harness is very thin, so anything can go over it). If I were to do any sort of multi day trip, I'd spend some time with some webbing and clips to make it attach to the backpack's straps/harness.

edit to add another shot of the bag, this time in use!!!

also think tank makes some interesting "digital holsters":
http://www.thinktankphoto.com/ttp_product_DgtlHlstr.php