Forget styrofoam… researchers are pushing syntactic technology to the limits of space. “Transparent aluminum? That’s the ticket, laddie!” (Scotty, in Star Trek IV: The Voyage Home) Imagine an aluminum foam that looks like solid aluminum, is just as strong, but weighs half as much. What could that do for air/surfcraft design? How about an aluminum foam three times as strong as the solid? Well… http://www.memagazine.org/backissues/january99/features/foams/foams.html
Most of this stuff is not cheap and too heavy. At 2lb per sq ft we are typically under what everyone else is gunning for. For instance the Ren 450 they talk about is about 40 lb per sq ft. However, if you have more money than Bill Gates I can get you some carbon foam. Sluggo