Observable - Interactive code examples/posts
DBeaver - DBeaver - Universal Database Manager and SQL Client.
TextSTAT - TextSTAT is a simple programme for the analysis of texts.
HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.
Calculist - The open-source, web-based thinking tool that facilitates effective thinking for solving problems.
DataGrip - Tool for SQL and databases