Day fifty four: A picture of the one thing you would bring if you were stranded on a desert island.
This question is so hard. I mean- there are so many things that factor into this situation. :) That being said here are some ideas.
A lap top. Not really practical because the battery would die and then would be a hunk of junk but in a fantasy situation this would be good!
In a little more realistic situation a radio would be good. Not only for entertainment but serves a more practical purpose as well.
And for the most practical answer I would chose this. A solar power water purifier. Great to have but not very fun! :)