Memory cardsOne of the beauties of digital photography is you can take lots of picture without spending a fortune getting them processed. The limit really to how many pictures is the capacity and number of memory cards. If your photographer use SD cards, get him or her a few more and perhaps a card wallet to hold them. Right at the moment 2GB & 4GB cards are the best value and hold decent number of photos (even RAW) However check that the camera can take SDHC cards (HC is for High Capacity)
USB Memory Card ReaderYou don’t need to buy the expensive ones, a simple all in one card reader with a USB plug can be stored in you camera bag. Then when you are on holiday or you are out and forgot your cameras upload cable you will have a backup.
Baby TripodsThere is a multiplicity of these from tiny desktop legs, that only support small compact cameras (not larger DSLRs), to the unusually named gorillapod, that has flexible legs, that can even be wrapped around a stable object but only a 325g lifting capacity.
One nifty small tripod-ish support that is a fraction dearer than my under $20 limit is the manfrotto pocket support. Its strong enough to support most grownup DSLR but small enough to leave on your camera.
Dust CleanersNotice I haven’t used the term lens cleansers, that is because most lenses these days are coated with specially formulates but thin anti glare and flare coatings. these layers are very easily rubbed off with even the softest cloth. Also it is a good idea not to use and liquid lens cleaners on your lens or even the LCD screen on the back of the camera. A soft micro-fibre cloth, not a paper tissue which will leave troublesome fibres everywhere, is generally all that is required to keep your camera body clean. An old fashion brush and blower are also useful.
Dust on the cameras sensor is a different matter and the camera owner should consult his/her camera manual.