Does it Exist? Musings on data backup when travelling...

I think I'm pretty much sorted for my trip to France next month... I have places to stay booked, the EuroTunnel booked, a rough route planned, and (while I haven't ordered them yet, as I'm just waiting on confirmation that I have the right bits list) a motorbike mount for my phone planned to act as a GPS (and a power lead to run from the battery to keep the little blighter running).

What I don't have is a decent data backup. I'm planning on taking 3 cameras;
1) Sony HD Camcorder
2) HDHero GoPro 2
3) HDHero GoPro 3

(I couldn't quite justify the dedicated HDHero drone, but assume one will be in my life soon...they are doing a new version with an auto-stabilized gimbal, which looks awesome).

(also, I didn't get in on the If I Had Glass Explorer scheme, though not for lack of trying. I can't think of a better way of getting POV motorbike shots than that...also it would be an amazing GPS for a motorbike).

So, I should be generating a fair bit of data. The intention is to record during the day, then in the evening, at base-camp to edit the footage down using a fairly robust app on the Nexus 7, before uploading it on the free WiFi at the base-camp. My concern is that HD video takes up a shed-load of space, and while you can download data from a memory stick/SD Card to the Nexus 7, you can't write it back (unless you root it, and I had a very close call bricking the thing). As such, I've been trying to find anything that can copy Flash Drives without having a PC involved...that way I can copy the camera raw data to cheap USB Drives, and just keep the Nexus 7 for the edited versions.

The closest I seem to have found is this box of tricks, which will probably do the job, but is a tad expensive for what I want to do (UK Price is about £80).

My other option (less favoured, as I'll be on a motorbike, and so space is at a premium) is to resurrect my netbook, and use that. This has a double-downside in that it pretty much means I'm limited to working with a mains power supply, whereas the N7 can be charged from the bike if need be.

The final option would be to buy loads of SD cards (and of course the custom Sony offering...thanks Sony!) and swap as an when I need to...that is viable, the main challenge being that GoPro's throw a lot of data out, so need the more expensive Class10 SD cards (and I've actually had one fail to record due to the bandwidth limit on a cheaper Class10 card...they really are violently powerful little boxes of tricks). Having expensive SD cards sitting around storing data grates with me...

I do really wish that Google/Acer/LG had seen fit to add Mass Storage Drivers to the Nexus 4 and 7...it's the only downside to them really, and would have resolved this headache in a single move.