I recently (last week) took delivery of a Zenithink ZT280 C91. Its a 10″ android 4 tablet. Total delivered cost around £100 from China via Alibaba.
Brilliant, great screen, stuck a 32gb sd card in, filled with vids, music and have loaded lots of games from the Humble Android Bundles and the Market/Play store.
edit to add: A “killer” feature is that it can act as a USB host, eg, can just plug in a USB stick, keyboard, bluetooth dongle and have it use them like a PC would. Sticking a USB SD card reader in and browsing pics from SLR Cameras memory card on a big(ger) screen then and there is all kinds of awesome.