the fact is the ISPs should be filtering this sort of stuff out but NTL can't be bothered to spend any money on this. Both BT and AOL offer this as well as AV scanning on mails. So do hotmail and that's free !
until the ISPs start to take responsibility there's not alot we can do.
To use the ISPs reasoning when a road is busy with traffic i should take responsibility for this and build a new one myself