Sorry if this offer has already been discussed , but I just stumbled across it on Vodafones site , and thought it deserved a mention

http://shop.vodafone.co.uk/shop/mobi...mpatible=false

I seem to be constantly asked about these Dongles , and so far have been warning people that they need to choose carefully , to get the right balance that suits them , in terms of contract/PAYG , overrun costs , coverage etc - they tend to get a bit confused by the end of it !! , but this looks like a pretty good deal to me , no worry about over-run , just simply top up £15 for every GB you use !
Not the cheapest plan , but a good combo of PAYG cheap purchase price , decent network (spit ! ) and 'safe' pricing - makes this a good buy IMO !