Important note: you only get one cup! If you want to have two and fit them together, you'll have to order two, probably in different colours.
An espresso cup shaped like half of the symbol for yin-yang. Bring some balance to your espresso. This should comfortably hold about 70mL (2½ fl. oz.), but that might vary depending on the glaze thickness. There's also an "clockwise" variant, which may be more comfortable depending on which hand you hold cups in: http://shpws.me/pZUS And if you prefer something bigger, there's a mug-sized version too: http://shpws.me/pb9m