Entering online compertitions which require input of mobile number, this misreads as sending info on products, but is realy usless info that they charge you for, but you do not realise untill your bill comes in, the number to whach for is 80210 and probably others, this has cost me £36 extra this month and they will not end the texts even if you send STOP message, I had to change my number to end the extorsion. Your phone company will not help in any way to combat this theft, In my case Vodafone.