Does canon supply remote capture software for it?
My G3 and EOS350D both came with the "remote capture" program which downloads pics directly to a PC which is connected via USB - only prob is that the on camera controls are disabled in this mode (it also leaks memory like a sieve, but that's not usually much of a problem).
Unfortunately, expanded storage is regarded as a high-end feature. So, only professional cameras offer features like hooking up firewire drives, or the ability to save to network shares via WiFi.