Has anyone considered using SlideShare to host slides from talks? In much the same way arXiv hosts papers.
Truth be told, the slides are often much easier to absorb than the papers. Sometimes I will Google a paper and find 10 versions of the slides floating around.
These are usually hosted by conferences or on personal websites. Unfortunately, when the conference site or home page dies, the slides go with them.
Example: holographic entanglement entropy
It may be better to collect them into one place. Of course, this is a lot of work to maintain and perhaps can detract from the informal nature of the slides.