A free alternative to Google Maps?

Hello everyone!
I’d like to share a reddit post that I wrote a couple of days ago.

http://www.reddit.com/r/freesoftware/comments/237wzb/id_love_to_find_a_way_to_support_more_free/

I was thinking about building a free map where people can create new layers or contribute to existing ones (for instance a phone book, pictures, videos, earthquakes, wikipedia, …).
I would also like to generate revenue from the map, for example displaying sponsored content such as businesses. I want to do this in order to direct all the revenue toward development of free software. My idea is to support OSM at first, and use this as a starting point to support other free projects.

I’d really love to hear your opinions on this matter. Unfortunately I’m now aware of other projects possibly doing the same thing.
Please share the link to this page if you know somebody who might be interested in this idea.

Thank you!! A lot!!!

I would start here, Using OpenStreetMap, where you can find information on how to deploy your on map and also list of other services already using OSM and other related projects.

You can add your own layers over google maps or openstreet map and have paid links if you want. You are able to build plenty of customizable layers.

Thanks for your comment. Could you please elaborate more on “have paid links if you want”? What do you mean exactly?
Also, do you like the idea and would you like to help?