Well I've just seen the Nokia Lumia 710 is £199 on o2 payg...

current devices:

Sony Ericsson Live with Walkman WT19i:

Picked this up in December 2011, it's a HVGA display, white, Walkman branded, 5MP auto focus camera, and the loudest phone I have ever heard, thanks to it's dual stereo speakers. Cost me £80 payg from 3 uk after Quidco Cashback, it's also guaranteed an upgrade to Android 4.0 come March/April 2012.

Dell Streak:

Won this for £60.88 from Ebay, came with a cracked screen that has cost me £25 to repair, may be an old device, but it's a beautiful 5 inch screen, strengthened with Gorilla Glass, and has an official Gingerbread 2.3.3 build, which is pretty recent if you check current Android reports that confirm 30 percent of Android users are still using Android 2.2

X10 Mini Pro

won this for £34 from ebay, arrived running Android 1.6, which was quickly replaced with official 2.1, and then replaced with MiniCyanogenMOD7 2.3.7. It's a very quick QVGA device with a very responsive keyboard, 5mp camera, wireless n wifi. It's also my last Armv6 device as I have sold my ZTE Blade and expect to see a lot more Dual Core handsets next year, and with WP7 entering the payg market, I can see Armv6 and Armv5 devices not being released by the end of the year