pgAdmin - pgAdmin Website
DBeaver - DBeaver - Universal Database Manager and SQL Client.
MySQL Workbench - MySQL Workbench is a unified visual tool for database architects, developers, and DBAs.
Adminer - Adminer (formerly phpMinAdmin) is a full-featured database management tool written in PHP.
Sequel Pro - MySQL database management for Mac OS X
pgweb - Web-based PostgreSQL database browser written in Go. Pgweb is a web-based database browser for PostgreSQL, written in Go and works on OSX, Linux and Windows machines.