Thanks for the link Josh.
On this website are MP3 recordings of presentations. The topic for these presentations is political events/issues from a Socialist perspective.The source for the presentations is Marxism, an annual event in London, organised by the Socialist Workers Party. I am hoping to include other sources.
They average at about 5MB for 40 minutes of audio (download time approx 20 minutes @ 56k). To minimise download time they have been edited down to the main presentation (contributions from the floor and summing up cut).