A cheap data sim that gives you free data in exchange for watching adds.

So the idea is you buy the sim. login to the portal and watch ads (via wifi) and earn data credit which is instantly usable. You can also buy credit. It run off the 3 network in the UK. a bit like Tesco run off O2 and Utility Warehouse use T-Mobile (part of EE).

Sims are around £5 (£2.50 if your refered buy a refer so give me a shout if you want a referal). 

They are shooting themselves in the foot a bit with not having a nano sim out yet but I just cut my micro sim down to size.

http://www.sambamobile.com