I didn't know they made those outside of Thailand! Gotta get some of those in the US.

Kidding.

Fascinating stuff on the inq-hated wikipedia site on porous silicon, seems it was discovered in the 50's in america by accident, and is found that when hydrogenated to be more explosive than TNT, at cryogenic temperatures, and could possibly be used to propel satellites.
http://en.wikipedia.org/wiki/Porous_silicon

Another topical detail: Another positive attribute of porous silicon is the degradation of porous silicon into monomeric silicic acid (SiOH4). Silicic acid is reputed to be the most natural form of element in the environment and is readily removed by kidneys.