I haven't studied Physics for a long while, so I could be wrong - but I don't think that the speed of light is actually an attainable speed. True - time slows down as you approach this speed but also your mass also increases therefore meaning that the faster you go, the more energy you need to go even faster.
That's right- Einstein's equation "e=mc^2" (energy=mass times the speed of light squared). How much mass you have times the speed of light(186,000 miles per second-I think) equals how much energy you need to reach the speed of light. Problem is, the faster you go, the more mass you have. The more mass you have, the more energy for speed you need. The more speed(which you get from the energy) you have, the more mass you get, etc...
The speed of light is impossible to attain by yourself(or in a space ship). So you'd need something which has those inherent qualities of lightspeed(theoretically-a wormhole).
Now, I read recently that supposedly, as you near the centre(the middle) of the wormhole, you suddenly are on the other side(It's impossible to reach the absolute centre). So, if two spaceships were heading right at each other, before they hit, suddenly they've passed each other, and are each on their way out. Now, this is supposedly when you attain(and pass) light speed, and end up on the other side of the galaxy. But the theory goes, that if you were to break out of the worm hole, before reaching the end, this would send you on a journey through time(how to control the trip-I don't know).
Or, if you wanted to time travel(I hate that phrase-I don't believe that time is linear-it just appears that way, 'cause we're only traveling in one direction), you could just do it like Kirk did on star trek, and do a slingshot around the sun at warp 9.99 /ttiforum/images/graemlins/smile.gif