The UK's biggest network operator, Vodafone, has announced that it's abolishing the 15MB data limit, set only a few months ago, in favour of a system by which customers can "browse the mobile internet as much as they like" for 50p a day on an ad-hoc basis. It's a system that works well, and one which I use often with a whole brace of PAYG SIM cards. Digging deeper reveals that the new limit is 25MB, not a massive increase, but this is now a 'fair use' figure rather than a hard-coded limit and (thankfully) you won't be charged extra without contact first from Vodafone to warn you about excessive data use (e.g. if you tether to a laptop or similar).