Physicists R. Nemiroff (of APOD fame) and his student Teresa Wilson, recently published their results of a grand internet search to look for evidence of time travelers. In a nutshell they were looking for ‘time traveler activity’ over the internet, say a timer traveler used his time machine to move back in time and say…send an email, or put information online about world events that just happened way before it actually did. Time travel to the future is allowed by special relativity, however there is much debate if we can actually go back in time.
The search as you may have expected didn’t turn out much …. but made for a pretty good story.
To read more you can download their preprint paper here