overall I have been lucky on my trips, not having the forementioned pack up in rain, ride in rain and setup wet...blerk.
I have however had some extra days to take a day off, and also have used cheapish B+B or motel type places when its been a very wet day and I could do with a break (and kinda figured that on a trip, as we are usually being frugalish anyway with camping and cooking our own food, a night or two in a cheap place is not the end of the world.

the answers already put down are pretty much spot on for me, but as Ive said, in the summer touring Ive done, rain has seldom been an all day or multi day thing.(must touch wood on that one though)