Well, largest payment I have ever got from a dialer program was $5-something, and that was basically a thrown out money, because that did not cover banks commission for cashing in checks.
At some pint in past dialers was all the rage for those who would want to pay for porn, but either did not have credit card or did not want it to show up in their bills. For webmasters that meant mostly any traffic outside the US of A. Also, that was more like for dial-up users. When broadband over cable and DSL started to reign, it was not working like that. As far as I remember, it was possible to call up certain number, and you would get access to a site as long as you don't hang up the phone. Your phone bills would be ridiculous of course. Like $2 per minute or so.
As far as Europe goes - nowadays indeed you can pay through your mobile phone with SMS for a lot of things - from parking to access to porn sites
The problem with SMS payments for porn sites still remain:
1. There is no way to confirm your age. A presence of credit card is used as a confirmation of age (although not always true), because normally you have to be 18 to get a credit card.
2. Network limitations - Its complicated to set up a billing system that is working on multiple networks over orders.
HTH