Most of the software I use on daily basis are Free and Open Source.
I’m running Debian Stretch on both my Laptop and Home server. My Raspberry Pis are powered by Raspbian Stretch Lite (Headless). I have a cloud server running Debian at Linode. I have a couple of Virtual Machines on my Home server powered by KVM, running Debian Stretch and Archlinux.
On my laptop, I’m now using Cinnamon Desktop Environment with LightDM. On my Home Server, I have i3 Window Manager installed. I spend most of my time in rxvt-unicode(urxvt) inside a tmux session. I use quite a lot of command line based utilities like moc, ranger, pass et cetera. I like Vim a lot and always have at least one Vim instance open and I do all text editing in Vim. For browsing the web I use Google Chrome browser. Thunderbird is my email client and I use a very popular Enigmail extension to sign/encrypt/decrypt my emails using GPG key.
I run a local DNS Server on Raspberry Pi powered by BIND 9 which combines Google’s Public DNS with that of Opennic and resolves local domains. And as I run multiple machines locally (Physical and Virtual) which runs web servers, I have Nginx Proxy setup on Raspberry Pi which forwards web requests. Raspberry Pi also runs a ddclient, which is dynamic DNS client. I run several Docker containers on my Home server. I use Cgit on my person Git server.