Some questions in return:
How do you define "effective"? What result are you looking for?
How do you plan to distribute the business cards?
What sort of business do you have?
If you're asking whether leaving a stack of business cards in a rack on the counter at a restaurant, grocery store or other local business is going to drum up a lot of business... well, that will probably depend on the kind of business you have and the kind of customers who generally come through the business where the cards are displayed.
For instance, having a business card advertising a business that sells nothing but one-of-a-kind antique Chinese porcelain pieces might not be such a good fit to put out on the counter at an auto repair shop. Unless the auto repair shop specializes in luxury automobiles, in which case it might be a better fit than it appears on the surface.
But a much better -- and probably more effective -- use of those business cards might be instead for the owner of the porcelain shop to head over to the interior design trade show and exchange some cards with interior decorators and designers after engaging them in personal conversations to qualify them as good leads.
It all depends on where and how the cards are distributed and what you mean by "effective."
--Torka