Inorganic fullerenes-- recently discovered non-carbon analogues to buckytubes -- are notable for a few important reasons: they can be produced relatively inexpensively, are chemically stable, and tests so far show them to be non-toxic. Moreover, they're incredibly strong. According to ZDNet, materials made from inorganic fullerenes have remarkable "shock-absorbing properties," making them suitable for (among other things) new kinds of lightweight bullet-proof armor.
During preliminary tests, these materials, which are five times stronger than steel, have successfully resisted to steel projectiles generating pressures as high as 250 tons per square centimeter.
The material tested, which for now can only be made in small quantities, is Tungsten Disulfide (WS2); ApNano, a company formed to work with inorganic fullerenes, plans to shift to Titanium Disulfide (TiS2) soon, as it will be lighter and stronger than WS2. Although ApNano is promoting the material as a potential new form of armor, strong, lightweight materials could have numerous important applications, including bodies for high-efficiency vehicles.