Edge wine glasses and champagne flutes - my favorite
Edge Wine glasses - Crate and barrel
Posh Party Supplies - Clear Tiny Square Wine Glass - 2 Oz. - 96 Plastic wine Glasses, $41.35 (http://www.poshpartysupplies.com/elegant-dinnerware/posh-minis/clear-tiny-square-wine-glass-2-oz-96-plastic-wine-glasses/)
Fineline Tiny Temptations 6410-CL 2 oz. Tiny Barware Clear Plastic Square Wine Glass - 96/Case
DIY: Cut Square Glass Bottle In 3 Simple Steps File smooth with 80 grit then 280 grit paper
Shop Nattie Red Wine Glasses, Set of Nattie's tulip-shaped bowls square up just a bit to put a modern angle on classic glassware.