I have a compact digital camera - Fujifilm Finepix E550 which runs on two A A sized batteries.
I gave up using single-use cells with it due to the cost, and have been usi ng NiMH cells. Whilst these are useful in many applications,I find that the y are pretty poor for the camera as they only return around 20 pictures bef ore the camera decides they are flat. I assume this is due to the lower vol tage per cell.
I bought a set of four NiZn AA batteries and the matching charger (currentl y on offer for 6.99 each) from the holiday camp in Hi-de-hi as the NiZn che mistry has a higher voltage than the NiMH cells. Although the overall capac ity of the NiZn cells is apparently lower, I have been able to fire off 130 pictures so far, 100 with flash, and the unflashed 30 having a full lens-z oom between them (i.e. from widest lens - take picture - zoom out fully - t ake picture - zoom back - picture, etc.).
This was indoors at about 18 degrees Celcius. I have no idea how dramatical ly colder temperatures will affect the performance, but so far I am quite h appy with them.
Hopefully this will be of use to someone else who is maybe considering rech argeables for high-drain devices.