I have mentioned TOra before. For those that are using Oracle, you will need a tool like Toad to help you in your day to day Oracle tasks. TOra is a ideal alternative for Toad if you are looking for open source solution. However, before this TOra is only available for *nix platform only. Now the 1.4 snapshot is available for Windows.
TOra is a Toolkit for Oracle which aims to help the DBA or developer of database application. Features PL/SQL debugger, SQL worksheet with syntax highlighting, DB browser and a comprehensive set of DBA tools. TOra also includes support for MySQL, PostgreSql and ODBC as well.
You can download the 1.4 snapshot from https://sourceforge.net/project/showfiles.php?group_id=16636&release_id=586904