If you have an Android phone, Barrr is a wonderful game by FireDroid. It is available in the Android Market or direct from their site via a QR barcode. It was developed by two Dutch students as part of their degree program in Multimedia: Mariecke Kouwenberg and Roy van der Veen.
Barrr is a lighthearted simulation of a pirate bar complete with tattoo station, video games, karaoke, and a dart board. Each scenario takes a couple minutes to complete, making it a great diversion for short interludes.