This is something I've thought about on and off for awhile.<p>For completeness, I believe that the speed of light is a hard limit (and no I don't believe in any end-runs around this like warp drives, folding space or wormholes). Secondly, I accept the laws of thermodynamic.<p>Given this traveling between stars takes an incredibly long time. At a high percentage of c you get time dilation but that's not actually a practical travel speed for a few reasons:<p>1. The energy cost of accelerating to 0.99c and decelerating at the other end is extraordinarily high;<p>2. If you even can get to that speed, small objects in the interstellar medium become life threatening; and<p>3. Beyond about 0.86c gas in the interstellar medium actually creates drag making acceleration even harder.<p>Given the reaction mass problem, it creates a big question of how you'd actually travel between stars. The more you carry the more energy you need to accelerate and decelerate it. It's likely you'd need fusion at a minimum and possibly some far-future tech (eg antimatter, black holes).<p>So what do you do? Well, there are rogue objects not bound to any solar systems. We've seen some of these. We can't easily detect them so can only speculate on how many there are but it's likely to be a fairly large number.<p>So what if you opportunistically wait for one of these objects to travel through the Solar System and then hitch a ride? Imagine a planetoid 100 miles in diameter. That's likely all the resources you'd need. It then becomes less of an issue that it might not reach another star for 100,000+ years because your attitude is that this is a new home.<p>Obviously you still have to match velocities with this object but that's vastly easier to do with a bunch of people and equipment than it is with those same things plus all the same materials that are already traveling at intersellar speeds.