I spent 12 years (1988 - 2000) creating Project Management software at Primavera Systems , and since I'm an open source guy, I always figured it was a matter of time before an open source alternative emerged that was good enough to disrupt Microsoft Project.
Well, that time has come. I recently downloaded Projity's OpenProj, and for those who still think that "open source" means less feature/function....well think again.
OpenProj offers all of the typical project management bells and whistles found in products like Microsoft Project...only in a more approachable, open source offering. After installing OpenProj, I started off by opening some of my old Microsoft project files and poof...they opened up right away and looked great.
I still need to play with it more deeply, but the product feels nicely polished. This, of course, made me curious as to who is behind the company. A look at the management team yields expertise from Scitor (which always boasted nice graphics) and WebProject (one of the early hosted, web-based solutions).
I have not yet tried out Projity's Project-ON-Demand, which is their hosted SaaS (software-as-a-service) offering, but at first blush, it appears to offer much of the feature richness of OpenProj directly in the browser.
So for those who don't want to install software, you can use Project-ON-Demand. For those who prefer a desktop app, OpenProj is a great choice.