SQL Developer
The Universal Database Frontend

SQL Developer is a database administration and query tool that provides a single consistent interface for various databases.
Visually navigate through your database structure, create and execute SQL queries and scripts the easy way. Or reverse engineer complete data models with the integrated diagram editor.
Your quest has ended. Why use a lot of different software tools to get access to your favorite databases? Use a cross database tool on any platform running Java with one frontend.
Latest announcement
SQL Developer 2.3.0 has been released
See the release notes for more details.