After all, if the Voyager 1 probe - the fastest-moving man-made object in space - was aimed at Proxima Centauri (the nearest stellar neighbor), it would take in the ballpark of 100,000 years to get there. Ouch. If you think we humans are naturally quarantined from the rest of the galaxy, you wouldn't be far wrong.
In terms of cosmic timescales of millions or billions of years, 100,000 years is tiny. But for human experience, this is a horrid situation. Thousands of civilizations have come and gone in that time frame; waiting 100,000 years to reach another star is just plain silly.
No. We need another way. We need new ideas for spacecraft propulsion. We need new concepts for spaceship design. Hell, we need the USS Enterprise! (And I'm not joking.)
Hence why DARPA, with the help of NASA, set up the whole 100 Year Starship Study in the first place. Be sure to keep up with the mind-boggling Icarus Project, a team of scientists and engineers all providing original content to Discovery News, describing every aspect of a 50 year mission to another star. Space may be big, but it doesn't mean we can't think big. Icarus is one of the hopeful contenders for the 100YSS $500,000 prize to further develop their concept.