The only thing with the Archos is that USB Flash drives at 16Gb are getting cheaper - I've seen them under $100, and unless you don't like the media player in the nokias you don't need the multimedia function. Unless the $180 price Amazon was quoting was wrong. http://www.meritline.com/usb-hdd-enc...rnal-host.html
combined with a 80+Gb drive should work and be less expensive (I don't have it yet to test because I'm away from home and my 2.5" drives).

Note it comes with a 5 pin mini A to USB F, but I think it is the kind that won't fit into the n800 - the real OTG cable. And this "case" has copy functions to pull (and maybe push?) files to or from another device.