Pogoplug Mobile (streaming Network Attached Storage) personal 'cloud' storage for $49.99 + free shipping
So this device takes your USB hard drive and/or SDHC card and puts it on your network(VIA eth.) and exposes a protected port to the internet via their own hosted portal directly back to your device.
I've read this device is very easy to set up, and makes it seem like your ipad or android tablet/phone has limitless storage. YMMV
The video in the link will explain it.
The upside? You can attach a very large drive to this and no more monthly fees to amazon or google.
I'm sure at your house in your own sphere of influence you can access it locally at speeds faster than 4g, or at least more reliably.