Combined PPC management for Google/Yahoo/Bing

Hi All,

I’m looking for a way to manage all of our PPC programs for Google/Yahoo/Bing all in one interface.

Does anyone have any recommendations for this? We’ve looked at a couple of paid options, but most of them seem a bit exhorbant. We’re not against a paid solution, but $500+/month for a program that still needs to be managed by us seems like a bit much.