This page showcases some of the advertisement possibilities of the Flash Players. I've used advertisements from the small startup SpotaJob, for which I did some design work recently.
Select an example at the left side.
In large, advertisements must be inserted by using a playlist (in RSS, XSPF or ATOM format). A playlist entry can be designated as advertisement by setting it's <category> element to either preroll, overlay or postroll. Preroll and postroll ads can be in any media type the players accept, overlays can only be in image formats or SWF. Advertisements will not be displayed in the playlist, and they cannot be scrubbed. It is possible though, to pause advertisements, or to start them through the javascript API.
These advertisement examples contain two different SWF files. Since their creation is a bit difficult, I hereby have the source files of both the overlay SWF and the postroll SWF. The main trick is the creation of a transparent background rectangle so the players can set the correct width & height. Note that the postroll SWF dynamically loads the most recent job offers from an RSS feed!