Check out the online shopping site PriceGrabber, which has created a sort of online pledge campaign against pop-up ads and spyware:

Pop-Up Free Code of Conduct

1. You do not serve pop-up or pop-under advertising on any of your Web sites.
2. You do not offer services that install hidden, ad-supported programs onto users' computers on any of your sites.
3. You do not knowingly work with companies who engage in advertising through spyware, hidden ad-supported downloads or similar ad activities, to drive users to any of your Web sites.

Sites that agree to do this can download a logo and display it on their site. We at WebWatch applaud and support this sort of thing, though we do caution that these kinds of logo/seal of approval campaigns have a major vulnerability: they can be faked. Just ask TRUSTe or QuackWatch. That's the major reason we (and Consumer Reports in its 75-year history) have been reluctant to do seals. The other big problem is that you have to police them -- anybody remember Web Trader UK? Actually, the Web Trader brand appears to have re-surfaced under the aegis of a U.K. branch of the Direct Marketing Association.

Meanwhile, we'll ask PriceGrabber itself to join competitors BizRate and Shopping.com to take the Consumer Reports WebWatch pledge.