How cool is this...

[Teege]

http://ntrs.nasa.gov/search.jsp?R=20110023492

To infinity and beyond? Okay, so maybe just Neptune...

[Tazhyngarth]

and enabling interstellar spaceflight by the end of the century

I can only hope I live long enough to see some prototypes of this....

[Blitzwing]

If money were no object, given the current rate of technological advance we've been seeing over the last generation, I'd think we could see a prototype test within my lifetime(I'm 40 now, heh)....   8)