I use a Lowepro Nova 3. You can adjust the middle chamber to exactly fit a Rollei and the side chambers are perfect for film and light meter and accessories. The outside pocket on the back is perfect size for passport and airline tickets.

I take a lot of vitamins and herbs and they mostly come with a silica gel pack. I have a tupperware container to hold my enlarger lenses in the basement and toss the gel packs in there and replace them now and then. The camera bag I keep up stairs where humidity is generally below 50%.