WebSphere Application Server for Developers

IBM's WebSphere Application Server (WAS) is the company's flagship Java EE 5 product used in production environments worldwide.

As you would expect for a product representing over 10 years investment from Big Blue, it comes with a license fee to match. However, if you are willing to forgo formal support, and can live with the developer license offered, you can now download the full application server at no cost!

The "WebSphere Application Server for Developers" package for Windows or Linux is available as a download directly from IBM. Bear in mind that WAS weighs in at 788 MB, so downloading over a 1.5Mbps connection is likely to take about one and a half hours.

Go and grab it, and try your software out on a runtime that matches the production environment. In place of formal support there are WAS developers answering questions on the open newsgroup.