Read on Joel on Software about this pure css slideshow called s5. It seems like it would be a good tool for one’s client extranet, in sweet compliant CSS. Think of it as an engine for creating slide-style presentations on the web, just the kind of thing that might be nice for presenting a series of mockups or even online proposals. The default templates are not much to write home about, but you can of course customize them.
Alex Velickyi 
Not bad. But I think it’s better to use flash.
In my opinion galleries and slide shows should be dynamic.