One of the recipients of a 2006 Victoria, Australia's State of Design Award -- specifically The City of Melbourne Sustainability Design Award -- is Katrina Logan for her LUMI Illuminated Rainwater Storage.
The satin acrylic container is targeted towards "the inner-city design community." Logan "envisages the balconies of high-rise developments as LUMI's ultimate destination." While the feasibility of collecting water on balconies typically located below other balconies may not work too well (making it perhaps more appropriate for backyards), it's nevertheless a great idea: making water conservation attractive by making something that's, well, attractive.