If there's a cheap medium that can supply high quality content for pennies, it is the DVD which proves that it is really versatile.
IBM has made an application for a "System and method of providing advertisements during DVD playback" back in February 2006 but it has only recently surfaced.
The abstract reads as follows A method wherein contents of DVDs may be restricted based upon purchased certificates is provided. The certificates allow for secured information on playback. Specifically, whenever a DVD is to be played, a certificate is consulted to determine whether the content of the DVD should be played with or without commercial interruptions. If the certificates provide for commercial interruptions, then commercials can be obtained from an online service that renders commercials on demand, or from the DVD itself. In such a case, the content of the DVD may be interspersed with commercials.
Implementing adverts in DVDs (or indeed in any other optical drives) and using OTA (over the air) updates to bring in new advertising might prove to be a surprising hit at a time when Internet Service Providers are clamouring for more investment to boost their networks.
This could mean for example, getting full version of Friends on a couple of Blu Ray HD discs with adverts or short advertorial being delivered either à la Google Videos (as overlays) or as ticker ads or as traditional advert breaks.