I really must get round to joining an online video rental thing again soon because some of those I'd like to see the extras/commentaries on, but don't want to own.

Although what these people don't consider when they come up with the names for the extras, is that they're only explained in the box - and online DVD rentals don't come with the box.

I liked The Ark and Terror of the Autons and Spearhead from Space.