When Google launched the Lunar X Prize in 2007, the company planned to scrap the whole thing if nobody still won by 2014. Luckily, the company has realized just how tough (and costly!) it is to develop a rover, send it to the moon, drive it 1,640 feet and then transmit "HDTV Mooncasts" back to Earth (whew). So, it's now extended the deadline -- again -- to December 31st, 2016, so long as one of the participants submits a launch plan by December 31st, 2015. "We know the mission we are asking teams to accomplish is extremely difficult and unprecedented, not only from a technological standpoint, but also in terms of the financial considerations," said Xprize chairman Robert K. Weiss.