For joysticks, I got a good suggestion that I first get the joystick properties to get the max X and Y values for the stick. Turns out that 0-65535 is not a fixed value. Of course, I should've figured. Nothing's fixed in Windows :)
In the aim of sharing, I'm gonna give out one of those stupid little utilities that I use all of the time. This little one's called OptBmp, and it's really nice if you use tons of 256-color bitmaps in your games. I realized quite a while back that most paint programs save out a large color table even if your picture doesn't use too many colors. OptBmp analyzes the bits in your bitmap, removing unused color-table entries. It's not a big savings in bitmap size, but the savings can add up if you use tons of bitmaps in your apps. In theory, this utility could break programs that have brain-dead bitmap loaders, but I haven't found one yet.