I use the
JWPlayer which supports Flash and HTML5, meaning your videos will show on devices that don't support Flash or workplaces which don't allow it.
It's a bit pricey for the sinlgle commercial license (€59) plus another €9 if you want the HD plugin, but well worth it. I have a bulk license which is considerably cheaper per site, which design and hosting clients can use...but if you have multiple sites it gets cheaper the more licenses you need.
Ideally you want to put your video files on a server that supports HTTP PseudoStreaming (see the
JWPlayer Support and
H264 Streaming Module site) which allows automatic bitrate detection / switching (serve HD quality to high bandwidth visitors, lower quality to lower bandwidth, automatically) and seamless HD / SD switching (without it the video starts again when switching streams). But that's not essential and it works perfectly well without it.
I'm using it on Shaun's site, there's a single video demo link which he might share, otherwise wait to see it on his site :)