As Phil said - it depends on the domain name.
Domains that work very well with such a setup is:
* mis-spelled domain names (for eg: googel.com)
* keyword.com (because, sometimes people use the navigation bar to search for a keyword and are then forwarded to the keyword.com)
I myself have not had experience in making money with domain parking. But a few weeks back, Bill Myers made some cool videos about the topic. And I know a few people who do make money with domain names.
What they usually do is use
www.sedo.com to park their domains and earn some money through ads. But the bulk of their money comes when they sell a domain from their portfolio fo 3-4-5 figures.
So they use sedo.com just to cover their domain and renewal costs and then make the bulk of their income when they end up selling their domains.