Prosecute them
Well anyone in the UK who is sending electrical waste to the landfill is actually breaking the law - there has been electrical recycling legislation in effect for about the last 4-5 years - The Waste Electrical and Electronic Equipment (WEE :-)).
Poeple just need to get off their lazy fat arses and take the stuff down the local council dump/recycle centre where they will take it off your hands, for free too.
On the negative side, some local councils have just been stuffing a container and shipping it to some ****-hole in Africa to get rid of it, though they are being found out and jailed.