Arch Wiki has a huge list of applications for most things.
This is probably a subset of that.
Internet
- Firefox - for web browsing
- Transmission - for p2p
- Thunderbird - for email
- HexChat - for IRC
- Brief firefox addon - for RSS
Multimedia
- GIMP - for photo editing
- ImageMagick - for command line image manipulation (
convert something.png something.jpg) - Clementine - music player
- VLC - video player
- Audacity - audio editing
- Kdenlive - for simple video editing
Utilities
- Atom - text editor
- vim - you know.
- kitty - a terminal emulator
- Synapse - file launcher
- Redshift - color adjustment
Shell
- ZSH with oh-my-zsh
Documents
- okular - for pdf
- kchmviewer - for chm
- Calibre - for epub and everything!
Other
KDE - login manager, desktop environment, everything.