Piero Scaruffi's knowledge base: Massive music database.

AlternativeTo: Alternatives to software and apps.

CheckiO: Online game to learn Python and JavaScript.

Audius: Streaming platform like SoundCloud but better.

PCGamingWiki: Aims to list fixes and workarounds for every single PC game.

Wikispooks: An encyclopedia of deep politics.

Johto Redrawn: A group of artists re-imagining the Pokémon World.

Living Worlds: Beautiful dynamic pixel art scenes by LucasArts' artist Mark Ferrari

KOTORINOSU: My favorite Room Escape game series.

Free software that I really love and is much better than most (if not all) paid alternatives. Besides functionality and features, I lean towards software that is fast, light-weight, customizable, non-discontinued, easy-to-use, privacy-oriented, open-source and, in some cases, portable.

7-Zip Zstandard: 7-Zip with integrated support of the fast Zstandard algorithm.

Ant Renamer / Bulk Rename Utility: Easily rename files and folders.

BleachBit: Deletes unnecessary files, a good complement to CCleaner.

Everything: Unlike Windows search, it searches every file and folder on your pc.

MediaHuman Audio Converter: Easy-to-use audio converter.

MPC-HC / MPC-BE: Extremely lightweight media players.

qBittorrent: Lightweight and open source torrent client. Without adware unlike µTorrent.

ShareX: Easily capture or record any area of your screen.

SpeedCrunch: Fast and very customizable calculator.

TurboTop: Makes any window 'Always on Top'. Discontinued but still works.

Waifu2x-Extension-GUI: High-quality image and video enlargement based on the Waifu2X algorithm.

XnConvert: Fast batch image converter with actions and supports more than 400 file formats.

XnView MP: Image viewer with many basic editing options.