Username1 needs to get on this set! If it has anti-gravity built in it might just have time travel built in as well
...Though time travel in and of it's self is not very useful without high-speed space travel as odds are if you go back a decade the earth is not going to be in the same place it is right now. Of course even without space travel one might be able to time travel and land on earth if the earth's motion to whatever universal reference the machine is referenced to is cyclical. Then you would just have to choose which cycle is closest prior to the time you want to visit, and hope the cycle is short enough that you will live long enough to visit the point in time you wish to see...