I like the idea of technical content wrapped up in short, easy to digest peices - long webcasts are just too hard to watch without switching off. MS has been
publishing a series of these called MSDN Nuggets. You can sream individual talks (each is in the 10-20 minute range) or better yet, download a talk or even a month's worth as a zip file and watch them at your leisure. Individual talks range in size from around 2.5MB to over 5, while the months' download is around 40MB (April's is shorter at around 25MB). For folks looking to fill in the gaps, this is a cool idea.
I should point out these talks are from Microsoft UK. :-)