Vodafone mobile broadband dongle in pink. Price includes £15 credit (for 3GB of data for 30 days). Also 3% Quidco (44p) plus 28 clubcard points. Free delivery to Tesco stores or £5 for standard delivery.
My dad has a Vodafone broadband connection and it's very good for him - he gets much faster through this than he would through ADSL. The decent thing is that it's really easy to top up with a normal PAYG voucher, unllike O2 who make you use a credit or debit card. And you get Tesco, Nectar, Co-op, Boots, etc points on the top-up voucher as well.