This popular app has been downloaded more than 1.2 million times and is being used in more than 142 countries. It opens both Microsoft Project and Primavera files and can create Gantt Charts, Network Diagrams (PERT Charts), WBS and RBS charts, earned value costing and more. Operating System: Windows, Linux, Unix, OS X
38. GanttProject Replaces: Microsoft Project Professional ($999.95), Primavera P6 Professional Project Management ($2,500)
While not as robust as OpenProj or either of the commercial options, GanttProject works well for smaller teams that don't need a lot of bells and whistles. It creates both Gantt and PERT charts, and it can import and export files from Microsoft Project formats. Operating System: Windows, Linux, OS X
While it was designed specifically to assist the handicapped, anyone can use Simon to control the desktop and create documents without using a keyboard or mouse. Note that while some of the documentation is only available in German, the program does work for English and Spanish speakers as well. Operating System: Windows, Linux
This 3D animation tool offers professional-quality modeling, shading, rendering and compositing. Check out the Web site to see actual clips of movies and shorts made with Blender. Operating System: Windows, Linux, OS X
41. Cinelerra Replaces: Adobe Premiere Pro CS5 ($799)
Cinelerra aims to bring professional-quality video editing to Linux. It boasts a huge (and growing) list of features that make it, in the Web site's words, "a movie studio in a box." In addition to the main version of Cinelerra at the site above, there's also a community fork available from Cinelerra.org. Operating System: Linux
42. OpenShot Video Editor Replaces: Adobe Premiere Pro CS5 ($799)
This video editor offers an intuitive interface, with extensive tools for editing and compositing with high-definition video. Key features include chroma key (bluescreen/greenscreen), rotoscoping support, scrolling credits, compositing, custom transitions and more. Operating System: Linux
43. Kdenlive Replaces: Adobe Premiere Pro CS5 ($799)
While aimed at home users, Kdenlive still offers a fairly robust feature set of video editing tools. It boasts multiple audio and video track support, easy drag and drop editing and a wide range of transitions and effects. Operating System: Linux, OS X
44. CineFX Replaces: Adobe Premiere Pro CS5 ($799)
CineFX (formerly known as Jahshaka) combines a video player, encoding tool, and editing tool into one package. It doesn't have near the capabilities of CineFX, but it does the job for lower-budget projects. Operating System: Windows, Linux, OS X
45. Avidemux Replaces: Adobe Premiere Pro CS5 ($799)
Like CineFX, Avidemux offers a much smaller feature set than Adobe Premiere. However, it's very effective for simple cutting, filtering, and encoding tasks. Operating System: Windows, Linux, OS X
Open BlueDragon gives users an open-source option for working with the ColdFusion Markup Language (CFML). The site includes extension help and documentation to get you up and running quickly. Operating System: Windows, Linux
Kompozer aims to be an open-source replacement for Dreamweaver or Expression and offers WYSIWYG Web authoring capabilities. You can use it whether you know how to write code or not. Operating System: Windows, Linux, OS X
48. NVU Replaces: Adobe Dreamweaver ($399), Microsoft Expression Web ($149)
Calling itself "the number one free Web authoring system," NVU can help even newbies get a site up and operating within minutes. Its based on the same code as Kompozer. Operating System: Windows, Linux, OS X
49. Bluefish Replaces: Adobe Dreamweaver ($399), Microsoft Expression Web ($149)
Bluefishs claim to fame is its fast load and run time. Its a good option for Web designers who are very comfortable writing code. Operating System: Windows, Linux, OS X
50. SeaMonkey Replaces: Adobe Dreamweaver ($399), Microsoft Expression Web ($149)
SeaMonkey is slightly different than the other tools in this category, because it includes a Web browser, feed reader, chat and e-mail client, as well as an HTML editor. Its based on a lot of Mozilla code, so it should feel familiar to users of Firefox and Thunderbird. Operating System: Windows, Linux
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