One of my favorites!<p>And yes, there is a Memex extension for Firefox and yes it is Open Source IIRC and yes they have a funding model that doesn't need to include spying on user data.<p>I'm still somewhat careful though: as recent experience has told us being a paying user doesn't necessarily mean you aren't also sold as a product. In my case I have a research browser (a Firefox instance) and another mail, timesheets and internal apps browser (another separate Firefox installation).