Actually, if you go fast enough, you don't need life-extension.
I remember reading, somewhere, that if we could just reach something like 99% of the speed of light, the entire universe is only a year away, due to time dilation. I read that a long time ago, though, so it may be out of date.
Of course, I'd much rather find a way around having to accelerate, at all, like wormholes, or something. Between the acceleration time, the radiation issues, etc., there are many more problems with lightspeed, than just getting there.