Okay so my friend owns a coffee shop. She has attracted many customers by offering free wifi in her shop. Lately though, as usual, someone had to go and ruin it for everyone else, and start using that as their porn surfing location... so now my friend wants to implement some sort of content filter box so that she doesn't have to deal with people doing that. So does anyone have any experience with this type of thing? Could anyone recommend anything? We're also interested in adding a Terms of Service page that you have to click 'I Agree' on before surfing. Currently the only equipment in use is the cable modem and the aging Linksys wireless router... so I assume we're going to need some more equipment. EDIT: Some people on my other favorite tech site have recommended that I look into something called OpenDNS... does anyone know anything about it?