Yo, Watson.Hi, Jo. What's up?I want to visit Tokyo, Sydney, Manchester, and Reykjavik during a trip that takes 30 days.That's ambitious.I know, right? Can you help me figure out the best way to do it - which order I should travel through those cities for the cheapest flight itinerary and the least chance of being jet-lagged?Should I also optimize for seasonality, so that you're moving through each city at its warmest time during those 30 days?That would be awesome, Watson. Oh, one more thing - I also want to make a reservation at Jiro's sushi place while I'm in Tokyo. So make that the priority above other criteria.I'm on it, Jo.This imaginary conversation between me and Watson is an example of the type of interaction you could make possible during our new hackathon from IBM, the Watson Developer Challenge for conversational apps.