Another suggestion from Dan Frost (http://www.linkedin.com/in/danielfrost), who says: 'the claim is - "If you can type, you can make movies...". Now that looks like fun...'
My kids tried it out on a PC - choose your characters, type in the dialogue, then save the movie and watch your actors play in your movie. Fun, plenty of characters/backgrounds to choose from, decent text-to-voice software and easy enough for a 9 year-old to figure out alone. (One daughter was disappointed to find no Scottish accent option, so manipulated her English spelling to force something sort of north-of-the-Border, while the other chose a French option to voice her English text ... not quite what we language teachers are after ;-)
Relevance to language learning? I guess we could imagine learners making short movies, typing in dialogue, then saving/sharing the resultant animated clips. But some teacher input would definitely be required.