Last time i didin't use my computer so usually, but i have a few programs, that i want to see on every computer i use.
It's just one of the best software i ever seen. With this you can explore space and planets, make some researchers and calculations, and have fun with built-in scripts, that can make from your's Stellarium screensaver! I think, it's one of the best way to have fun with friends.
A simple sequencer, that have a lot of presets, samples and a few plugins. You also can extend it with VST plugins. Yes, maybe it's not so cool, as FL Studio, but working with FL, you need to search for samples and plugins on the Internet, here is you got enough to start make something. You can try it yourself, just look at pre-installed song examples and templates.
If i want to take experiments with sound, i conect Helm to my LMMS as VTS-plugin. It's have a lot absolutley free for use synthesizers, and you can create your's.
That's the best text editor that i ever seen. Comparing to Sublime Text, it's absolutley free for use and written on Pascal. It's have built-in package manager, themes, and a lot of customization options. This website being written with CudaText.
Free and opensource version of Aseprite. Works very well for me. Sometimes i like to draw some simple animations and pictures. Also have a lot of palletes preinstalled, so you can fun with it!
Very useful video editor. It's written on Python, but works very fast, and have a lot of options for your video editing and converting. Sometimes i need to convert Webm to MP4, but ffmpeg works slow, and it's hard to work with multiple files, so i fast can compile a few videos in one, and convert it.
Almost every computer i use have this software, i just cannot imagine operating system without that great collection of screensavers.