I would definitely go six or seven hundred years into the future. For one I would get a history of lottery drawing numbers and make sure to hit a big jackpot when I got back, so I would be very rich if I returned. It might be hard to track down this information quickly, but if there is still an internet it shouldn't be too hard to look up within such a timespan. Actually I would first put someone here in charge of maintaining a website that keeps track of lottery numbers, and then since when I get back I will be a billionare after winning two massive jackpots, I could use some of the interest from that to create a foundation that archives lottery numbers and other tidbits of information that I may find advantageous to know, so that I can record them in the future and bring them back with me. Additionally, it is probable that in six or seven hundred years the state of medicine and technology in general will be extraordinarily advanced, if pseudo immortality has been achieved I would probably stay. At least I would bring back as much information with me as I could in an attempt to advance the present day to futuristic standards.