With the Fields Permissions component you are able to apply
permissions over fields, making them invisible or readonly, with a
simple configuration system available from the list settings of
your list or through site settings.
The Fields Permissions component is availbable for
both SharePoint Foundation 2010 and SharePoint
Server 2010: please check out all feature's that this component can
provides at the product's
detail page.
If you want a live demo, feel free to contact us.