OpenProj is a free and open source version of the most popular (and expensive) project management application, Microsoft Project. Yes, that’s right, free. Not only can it create project files that can be shared with Microsoft Project users but OpenProj can actually open Microsoft Project files as well! It becomes in essense a Project viewer much like Adobe Reader views PDF files, except for one major distinction: OpenProject doesn’t just view Microsoft Project files, it allows you to make changes to them too!
Here’s a screenshot of OpenProj. Click to view larger image.
Download OpenProj here for free. This isn’t some restricted time-limited lame demo trial version either. This is the full monty! Full version, free without any catches. There is a web version that they sell called Project-on-Demand which is still a fraction of what Microsoft Project Web Access costs (not to mention the expense for SharePoint and SQL server which are required)!