Forget about MSN, Yahoo, and Google. But what other companies offer low keyword costs for advertises? Is 3fn any good?
Geraldm, the research has shown that the smaller ppc services and engines are more susceptible to click fraud.
I advertised on goclick.com some time back. Although the PPC is really cheap compared to google, i couldnt get any quality leads from there. Infact only keywords like affiliate program or business opportunities do well there. Another place is Bravenet. Although I havent tried Bravenet but it could be worth targetting their users.