Mark,
You have hit the main ones for our industry. There is a good open source GIS (I will have to check on the office systems where we use it). Steve in an earlier post mentions Linux, but it is an operating system and not an application or program. Still, it is a really strong and stable alternative to windows. It is probably the most notable open source code there is and is supported technically by a very knowledgable network of computer programmers. I find OpenOffice to be a wonderful word processor and spreadsheet creator. Gimp has made big strides and one of the few that read proprietary codes (like Photoshop). You have probably used some of the Mozilla open source programs like Firefox. We are still missing a good open source CAD and InDesign-type program. They are not perfect, and the risk you run by using them is their technical support or if the program falls out of favor. I still think it is worth supporting these efforts since many times their innovation spurs real change in the software world The mentality is not just ‘how can we change the face of the program to call it the next version and charge loads of money for it.’
On top of all that, there is the whole slew of Google Docs ‘cloud’ type programming.
I really believe we are on the edge of a major change in how we use software in our daily lives and in the design profession. Open source and cloud software will have a big part. I think it behoves us all to keep up with what is going on in the software world and not just who advertises the big glossy adds in trade magazines.
sorry- that was really more of a soapbox rant than an answer to your question.
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