A Roadmap to Interstellar Flight [pdf]

> Spacecraft from gram level complete spacecraft on a wafer (“wafer sats”) that reach more than 1/4 c and reach the nearest star in 20 years to spacecraft with masses more than 10^5 kg (100 tons) that can reach speeds of greater than 1000 km/s

Picking a nit: don't do this, don't mix units when making a comparison. They both should have been fractions of c, or km/s, and it would have been nice to see how long the heavier vehicle takes to make the nearest start. But don't mix units in comparisons.

And yes, of course I can figure it out, but it destroys the flow of reading.