spliit.app — Share Expenses with Friends & Family No ads. No account. Open Source. Forever Free.
CyberChef — The Cyber Swiss Army Knife; a web app for encryption, encoding, compression and data analysis
marimo is an open-source reactive notebook for Python — reproducible, git-friendly, executable as a script, and shareable as an app
pixian.ai — Remove Image Backgrounds
Free while in beta but a pretty reasonable payment solution
@thesephist advocates for Hyperlink maximalism suggesting that everything, including words, phrases, and documents, should be hyperlinked.
Notation automatically generates links between ideas in the user's notes, creating a rich interconnected web of information.