This is freaking amazing. While NASA's been working on thin-film aerogels, three researchers from the University of Texas at Dallas have been forming "free-standing carbon nanotube aerogel sheets for photothermal deflection." What does all that g(r)eek mean? It means invisibility, son.
I won't pretend I understood most of the jargon-filled ten-page research paper presented by Ali E. Aliev, Yuri N. Gartstein and Ray H. Baughman, but from what I gather, they use electricity to vibrate the aerogel material, which doesn't just turn invisible itself—it actually cloaks what it's surrounding. Have a look at this "Application of a nanotube sheet as a mirage-based concealment cloak [that] is demonstrated in water:"
The researchers made their breakthrough last year, though we have yet to see it pop up in daily life, of course. I suspect the research going is slow because every time they turn the machine on and go to lunch, they come back and can't find it.