Many universities make their lectures available for free online through iTunes U. This is a great source of material for professional development for translators and interpreters, particularly those hoping to specialise in niche fields.
iTunes itself is free to download and install on either Windows or Mac, and you don’t need an iPod to use it. (Short video overview here: paid subscription required). It currently provides free access to over 350,000 lectures, videos and handouts with exercises, notes and reading lists, delivered by some of the top experts in their field.
So for example, you could use iTunes to download law lectures in French aimed at French law students, geology classes in German aimed at prospective German geologists, and so on. This means you can use the material to acquire both language and subject-specific knowledge.
Most of the material on iTunes U is in English, even from universities in non-English speaking countries. But I expect this will change as an increasing number of institutions share their material.