Every Share Point 2010 is OData Server
If you have a SharePoint 2010 site you can get all the data stored within it as OData Feed. Like I have a site with URL https://sharepoint/sites/demosite, you just need to add this portion to the URL _vti_bin/listdata.svc.
This would give you the list of Entities within that SharePoint site.
Namoskar!!!