Please take the time to peruse the Source Forge and Open Culture links I just added to our resource list.
Source Forge is a repository of free open-source (nonproprietary or noncommercial) software made available to the public for free! We especially had fun with Celestia, a program that takes its users on a visual tour of the solar system in VERY realistic detail and allows for a variety of levels of space exploration. There is a category called "Home and Education" which is particularly rich but other categories hold promise for usable content as well.
Open Culture caught my eye because James Taylor is offering free online guitar lessons there! I am sure that there is other content there of interest to course developers. Again, the emphasis is on FREE for those tight departmental budgets!
Let me know if you know of any good resources we should add to our growing list! And please let me know if you find anything particularly fabulous in any of those we have already shared.