What is That? Tamarindo

This fruit(?) grows in pods hanging in a slightly curved shape and can be found at the market all year long. According to the internet, and the internet never lies, cooking with the pulp of the tamarind is used as a spice in soups and sauces. It is also an ingredient in Worcestershire sauce. 

It's mostly a food found in tropical places so I didn't find any Italian recipes using it, but I did find it in an Italian grocery store. Does anyone else cook with this strange food? Tell me about it!