Another company that i think does very well in open sourcing is Kitware. All their projects are open-sourced; and I know from personal experience that these are very good pieces of code that they just give out for free. Apparently, their strategy is that their flagship product (vtk) is so big that there is more benefit for a small company to have lots of other people looking at the code, using it and sometimes improving and committing back the changes; also, that there are just too many cool things that one can do with it, leaving Kitware enough opportunities to create customized products for a fee(of course, they also provide paid support services as well). For me personally, it meant that my monetary constraints (grad student here) were not a hurdle in my research.