Blue glass mosaic.
http://www.google.co.uk/imgres?imgurl=http://imagecache6.allposters.com/LRG/34/3483/AN86F00Z.jpg&imgrefurl=http://www.berm.co.nz/cgi-bin/postershop/item.cgi%3Fi%3D4741644%26l%3D1%26cu%3DUSD&usg=__Q2sJQram-CvOqLZtCN0sQItXf9U=&h=323&w=400&sz=46&hl=en&start=32&zoom=1&tbnid=aNxAEefv-zc1FM:&tbnh=151&tbnw=187&prev=/images%3Fq%3Dblue%2Bglass%2Bmosaic%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26sa%3DN%26rls%3Dorg.mozilla:en-US:official%26biw%3D1680%26bih%3D810%26tbs%3Disch:10%2C800&um=1&itbs=1&iact=hc&vpx=813&vpy=513&dur=470&hovh=172&hovw=213&tx=134&ty=96&ei=99S5TPLtKZCRjAeO5snXDg&oei=8tS5TPrTNYiSOt3V0LcI&esq=2&page=2&ndsp=36&ved=1t:429,r:31,s:32&biw=1680&bih=810
I did such bases in green for Kirai's spirits and they turned out pretty nicely IMO.
Also, for the cola bottles
http://www.cuddlypawscardsncrafts.co.uk/10-miniature-cola-bottles-742-p.asp