So i’m very much an adherent to the free software (fsf.org) ideals. Though following the initial proliferation of that idea via copyleft (gnu.org) and the birth of linux, which turned out to be a fairly significant paradigm shift away from proprietary software, the language subtly changed and the phrase “open source” ended up superceding the initial ideas of free (libre) software, encompassing far more than the narrower subset of explicitly copylefted code. But while there were gains due to that expansion, there have also been losses (at least in my opinion). While the additional “permissiveness” of the MIT license (and many other similar options) which didn’t “force” the issue of open-ness in the same way copyleft did was a positive in some sense (in that it resulted in wider adoption of some open source code bases, languages and other efforts), it also meant that (for those who wish to do so), open source code which is released under non-copyleft licenses may now be incorporated back into closed-source proprietary codebases, which in my (never humble) opinion is suboptimal.
But it is what it is.
Anyhow, i am a huge fan of debian and use it for my everday computing needs (2 laptops and a desktop (and likely quite soon a VPS as part of this family of websites as well)
So many of my favorite everyday computing tools are also instances of free software: emacs, firefox, chromium, konqueror, thunderbird, claws-mail, evolution, sylpheed, gnupg, kate, bash, ssh, konsole, okular, etc… i could go on and on (and perhaps i’ll come back at some point to lengthen this list significantly).