Sonic screwdriver! It effectively does everything. Except wood and make breakfast. I did try to do that at one point...but it does have an anti-freeze feature!

[ The Doctor looks up at Crichton as if it should not be entirely surprising the man has met Richard Nixon. Which, really, it shouldn't be that surprising. He travels in time and space! ]

Yes! I assisted him with the moon landing. Had some aliens that were trying to manipulate the whole thing... safe to say, however, he really is as paranoid as they say.

[ He stands up to full height. ] We could except we've got no idea what it will do to affect Moya's personal timeline. What if we did that and then she never ended up with your friends as prisoners due to this incident?