Tim mentioned cell phones and the lack of telemarketing calls on his, but really that's only because, at this point at least, the cellphone number lists haven't been sold. This might change in the near future, as several wireless providers have been considering selling their subscriber lists. It's hard to see how they could do this, however, since, unlike landline calls -- annoying enough -- spam calls to your cellphone would cost *you* money.
-- Harmon Seaver CyberShamanix http://www.cybershamanix.com