For camera/lens body (including screen but excluding lens glass), I use a pump-spray monitor cleaner (basically a mild detergent based solution - so no worries about solvents other than water). I also use blower-brush, stipple-brush, cotton/cotton-wool to apply the cleaner and then a micro-fibre cloth to finish off and lift any final remnants of muck/lint.
For lens glass, I use a blower-brush - if the glass still needs a go, I would use a speck-grabber for stubborn bits - if there's lots of crud, i would use a clean micro-fibre cloth either dry or with the same mild detergent monitor cleanser as above if the muck was a real problem. Have to say though, that I've never had to resort to anything other than the blower brush and on the rare occassion, a microfibre cloth to lift a greasy fingerprint or two.
Camera cases - all mine are of a 'cordura' grade style nylon and a wet sponge or flannel has always done the job. If there was lots of sand kicking about - I would attack it with the vacuum cleaner first.