Make site read-only; no downloads

Hi,

I'm using 2010 SP Foundation.  My user has a site collection that they'd like to make read-only.  By this they don't mean the SharePoint definition of "read-only" (users can download and read documents but cannot edit them.)  Instead they'd like the documents to open in the browser only.  They do NOT want the users do be able to download or save a copy.  Is this possible?

Thanks,

Kristin