Hi ian....also have you heard of 'Magic Lantern' software for canon cameras?
its a home made FREE software that runs/ boots off the memory card...so it doesnt install over the canon software.
The Magic Lantern software unlocks canon cameras and also gives you video and picture shooting options that we will never see in canon cameras for many years to come.
things like Motion Detect, good for taking pictures of lightening ect...
dual ISO picture taking ( i think this is now available in the latest canons) , too many options to list.
check out the website....
WARNING....may get addictive !