In a pitcher, mix pineapple juice, vodka, and lime juice, then chill until cold.
Rub lime wedges around rims of 6 martini glasses. Pour sugar onto a large plate. Dip rims of glasses in sugar. Divide vodka mixture among glasses. Push a few pineapple chunks onto each skewer and set one in each glass.
I served these for my birthday dinner. Although mind-numbingly simple, they were quite tasty. The sugar rim was fun -- I served it w/ (brined) BBQ chicken w/ lemon and marjorum, and a pasta salad. I wonder what they'd be like w/ a sprig of mint?