I signed up on that do-not-call list back when it first came out, thinking it would protect me from the bazillion telemarketer calls that I used to get (mainly during dinner!). And it seems to have worked great, for the most part. I still get the occasional call, but they are either from a company with whom I've done business before (legally allowed), or some small local company like home remodeling, or something like that. The very few times I've gotten a classic telemarketer call, I immediately asked them for their contact information, then told them I was going to report them, and they'd be subject to a $10,000 fine! That shut 'em up quick, and I'd never hear from them again.
Well this morning I got a really frustrating call -- it was a computerized voice, calling about mortgage loans or some such thing! I'd have to wait through the whole shpiel to get to a live person to demand to be taken off their list, and I don't have the patience for that. Grrrr! I thought I wouldn't have to deal with this kinda cr*p anymore. The frustrating thing about it for me is that I was working, writing away, and the call broke my concentration, which I find VERY irritating.