Ok, so first up, that space elevator. Science fiction? So far, so yes, but plans for a structure that extends from the earths surface to the stratosphere have existed since 1895, when Konstantin Tsiolkovsky dreamt of a modestly named ‘Tsiolkovsky Tower’ which would reach through the stratosphere into space. The basic premise is to create a ‘beanstalk’ style structure which would be tensile, or supported from above via a counterweight, enabling us to send resources or people into space, for a reason which isn’t abundantly clear at the moment. I guess it could solve some of our waste management problems though we're already in the process of turning the earths orbit into the world's largest bin.
So once you've made the first step and reached the borders of space, you're going to be pretty tired. If you can just hold on about ten years you'll be able to check into one of many space hotels being proposed by a growing number of billionaire hoteliers with eyes on the skies. The most wildly ambitious is the Space Island Project, which plans to use NASA technology to build a habitable structure 4-500 miles above the earth which can house 20,000 people by 2020. Once we tire of mere hotels, the logical conclusion is to look at our nearest neighbour for a solution. Plans for a colony on the Moon are closer to fruition than you might think, providing a second chance for humanity once we succeed in our long held ambition of completely ravaging the natural resources on earth. Potential pitfalls include meteors and the length of the lunar nights, which at 354 hours is good news for club promoters and bad news for insomniacs and everyone else.
Once we inevitably piss each other off on the moon, it's going to be time to think about an interstellar move. Long term mass migration is a problem on earth but factor in, well, space and it gets a lot more serious. Generation ships are a hypothetical solution to the problem of the nearest stars being thousands of light years away, the basic idea being that a huge 'Ark' style spaceship travels at a steady pace across the galaxy with passengers re-populating and training subsequent generations as they go, which might explain why the concept is a favourite among sci-fi fans. One of the best known proposals for such a ship was the Enzmann Starship which would drag a 12,000,000 ton ball of frozen deuterium at its tail which would be used to power the 'thermonuclear powered pulse propulsion units', all of which is utterly incomprehensible, look at this picture instead.
Of course, the holy grail of Space Travel and the proposal that causes even the mildest nerd to salivate is Warp Speed, central premise and abiding technology of the Star Trek series. The theory behind it goes, and you'll have to bear with me here, that space time is curved, meaning that a 'shortcut' could hypothetically be made by bypassing this curvature and travelling direct from one point to another through the very fabric of space and time. Quite obviously this theory is just a theory, and you won't be falling out of bed and onto Mars anytime soon but don't lose faith, if by some quirk of fate humanity survives longer than a couple of thousand years, you never know.
For now though, keep watching the stars, or Richard Branson.