Ok, before I thought that you needed all these separate things to output over Composite/S-Video, since Apple doesn't sell any miniDisplayPort-to-Composite adapters. It's pretty simple and I'm surprised I didn't think about it before. Retailers actually sell VGA->Composite/S-Video for really cheap, no more than $10 at most places. What you will need is:

o miniDisplayport->VGA adapter (sold by Apple)
o VGA->Composite/S-Video adapter (sold separately at electronics retailers e.g. The Source, RadioShack)
o Composite cable (yellow video cable)

Now you can start watching videos on your TV, if it doesn't have a VGA port, over regular Composite video cables.