Well, I'm going to assume that you mean a design for interstellar travel. Also I'd say the international space station and the rise of space tourism are both fairly exciting, but we're entitled to disagree.

 

The problem with iterstellar space travel is simple, using today's technology it would take far too long to get even to our neigbouring star systems. I'm sure no-one will disagree with that.

However we define "too long" in different ways, and in this context "too long" means the journey would take longer than any man's (or woman's) working life. Suppose that we had a motorized platform large enough to sustain a small society. In that case the following generations could be educated to maintain the platform and direct it towards wherever it was headed. If this was so, although we on Earth would not see what was started, finish, there would be survivors on the platform. This would require no improvement on conventional propulsion techniques. We may even take one of the smaller planets in our solar system, hollow it out, and strap engines onto the outside.h