Got multiple machines, but I think my most FOSS setup is a corebooted Thinkpad X230. The ME firmware was stripped, leaving it non-functional after the initialization. I replaced the WiFi card with an Atheros one that doesn't require non-free firmware. The GPU is by Intel Ivy Bridge, so no need for proprietary driver. Currently running Debian on it.

With that said, there are some components I couldn't get by:

• the EC firmware is pretty much a blackbox, even though I was able to unlock some part to make it work with aftermarket batteries
• the graphic ROM may still be proprietary (gonna have to recheck what my machine got currently) -- FOSS is an option as well but with less support
• even though non-functional, the ME is still on -- god knows what this thing does exactly
• CPU microcode

The rest of the components are pretty well-documented by the community if not by the OEMs themselves.

I would put 95% for this specific setup. However, if counting everything I got, not even close, as I need some proprietary components for living.

For example, my company gave me a newer Thinkpad to do work, which thankfully I got to install Linux on. I still have to run enterprise stuff from time to time, most of which are far from FOSS.

And don't get me started on tax form submission.