+
+I love the idea of an inflatable 1-mile long sign.... It will be a
+really neat thing to see it explode when a bolt  (or even better, a
+Westford Needle!) comes crashing into it at 10 clicks a sec.  
+
Pageos and two Echo balloons were inflated with a substance
which expanded in vacuum. Once inflated the substance was no longer
needed since there is nothing to cause the balloon to collapse.
This inflatable structure could suffer multiple holes with no 
disastrous deflation.
