HMV are currently selling off the Beatles album boxsets instore for £100 each. Bit of a bargain as the stereo boxset has a rrp of £180 and the mono of £210.
Cheapest I've ever seen them. Picked up the mono set (pictured) as it's unlikely the discs will ever be sold separately for that one.
Edit: HMV are clearing out a load of stuff - this just happens to be the best bargain at the moment in my eyes. Details of some other bits here: http://www.hotukdeals.com/deals/hmv-instore-sale-good-bargains-to-b/738654