Lover's Cups

Jackie Lee and Hyemin Chung of MIT Media Lab have a great project called Lover's Cups, a wireless-enabled pair of drinking glasses. Each cup can tell when someone is drinking from the other; when both are being used they glow to "celebrate this virtual kiss".

Lover's Cups, Jackie Lee and Hyemin Chung [MIT Media Lab]
Long-distance lovers can still drink together [New Scientist]