Inspired by http://www.thingiverse.com/thing:464463, this doodad transforms a 2L pop bottle and a smaller 300mL to 500mL bottle into a solar water distillery. The smaller bottle is screwed directly into the doodad. The 2L bottle is cut latitudinal. The moisture containing material is placed in the bottom section. The doodad with bottle attached is placed in the bottom section. The top section is placed over top the doodad and the entire apparatus is placed in the sun for the distillation to commence.
Look to the thingiverse page for an STL ot print your own.