This one (https://en.wikipedia.org/wiki/Chromebook#Samsung_Series_3) with the Exynos 5? In terms of value for money it was, in my opinion, the best computer ever sold. One of those cost £229 and was in constant use for about 8 years, carried around in a rucksack, used for e-mail, web browsing, video calls, iPlayer, editing files on Google Docs, ...

If they could make one of those that runs Debian with the security features of a Chromebook but without the Google dependency ... it would be too good to be true.

Yes, that's the one.

I did have mine set up to dual boot Ubuntu back then, it was a reasonably capable little machine. Wouldn't like to comment on the security.

As you say, it was rugged and cheap enough to throw around wherever, and you can do enough in ChromeOS to get by. I only eventually ditched it when updates stopped being available.