I'm sometimes need to copy/backup various media cards e.g. SD etc. and USB flash drives but it's a real pain to have to do it via a computer. I want to simply plug the card or USB drive into 'my device' which I can then press a button and copy all the data or maybe individual files to the back up device - several times a day in separate sessions - and then later read it and copy it to my own computer. The device will have it's own battery to power the USB (or maybe a various card reading hub) and built in storage which I envisage to be 128-500gb - perhaps an SSD to save power over a HDD. I know there are devices like this for photographers to use and I'm guessing something like the WD My Passport Wireless can do the job, but the wireless aspect isn't important. Any recommendations or pointers for such a device please? The device would need to be small for a laptop or camera bag.