Might be of interest to some people but Dash4it have an offer on for maps. (2 OS maps for £11)
......Buy any two standard OS Landranger or Explorer maps for just £11 (RRP £8.99 each)*. The offer also works on multiples of two (i.e. get four standard maps for £22, six for £33, and so on), so the more you buy, the more you save. You can even mix and match between Landranger and Explorer series.
Simply pop the maps of your choice into your shopping basket and apply code OS11 to get your savings.