For any given task that enough people have wanted to do before on a computer, there is a multitude of tools available to perform that task on Linux. Here is a small list of cherry-picked ones that I tend to forget (or that I want to promote :) ). As I use Arch Linux, some may be Arch-specific.

• pulseaudio-equalizer-ladspa. [Arch repos] Assuming you use PulseAudio, if you want to run a very simple equalizer over whatever comes out of your speakers, use this package. The GUI executable is called pulseaudio-equalizer-gtk.

• nload. [Arch repos] For nice graphs/statistics on current network usage (mbits incoming/outgoing). To show all interfaces, invoke it as nload -m; to show only a single interface, use e.g. nload enp3s0f1.

• paccache. [in pacman-contrib] To flexibly purge package files from the Pacman cache. Pacman proper has --clean, but paccache allows you to remove e.g. all but the most recent three versions of all packages, ignoring stuff related to nvidia:

  paccache -r -k 3 -i nvidia,nvidia-settings,nvidia-utils,opencl-nvidia,linux,linux-firmware,linux-headers,cuda

  Also check out the other scripts in pacman-contrib, like pacdiff and rankmirrors.

• pdfpc. [Arch repos] Lightweight PDF presenting, with even some really esoteric features like detecting animated slides in a LaTeX beamer presentation (that doesn't really work in my experience). Multi-monitor support.