Some days ago, 2 March 2006, really great software
Oracle SQL Developer (known as “Project Raptor” through EA Release 3) is a new, free graphical tool that enhances productivity and simplifies database development tasks. With SQL Developer, you can browse database objects, run SQL statements and SQL scripts, and edit and debug PL/SQL statements. You can also run any number of provided reports, as well as create and save your own.
As for me, this software is a good free and cross-platform alternative for proprietary TOAD from Quest Software. This software has almost all TOADs features, it is efficient and has beautiful interface. The best features in this release are: PL/SQL syntax highlight and PL/SQL debugger.