Google's 3D spatial mapping tablet Project Tango is currently only available for purchase by invitation. Today some of those lucky individuals received an email informing them that the price of the tablet was being slashed by 50 percent from $1024 to $512. The email forwarded to Android Police also mentions that Google is "opening sales more broadly," and that this was the last chance for the individual to purchase the device reserved for them. Before you assume "more broadly" means you'll be able to buy one of those tablets in the near future, it seems like it's going to be a developer-only device for at least a little while longer. A Google spokesperson told Engadget, "we are opening sales more broadly because we want to broaden the reach to encourage more developers to join us on this journey." Google might be a tad bit gun shy about opening up devices like Project Tango to the general public after what happened with Google Glass.