In December 2004, Holger Beisitzer sold plastic grocery bags filled with helium at a German Christmas market as components of a piece called Flying Rubbish. This beautiful work succinctly discusses issues of both sustainability and artistic value. By taking seemingly worthless objects and modifying them only through the introduction of an invisible and nearly weightless gas, Beisitzer has asked the public to pay only for the artistic gesture itself, repurposing the bags as containers for an idea rather than physical commodities. Elegant.
Via Near Near Future
Related: George Kuchar's floating plastic bag and Sam Mendes' knock-off version.