Not in novel form, but there are actually two Star Trek (the Next Generation) episodes that involve time travel and Mr. Twain. I'm not a trekkie, but my buddy is and he has the "time travel" collection. They're "Time's Arrow" (parts 1 and 2). http://en.wikipedia.org/wiki/Time's_Arrow_(TNG_episode) It's fun hearing all the suggestions people have, Michael Minnesota State University, Mankato