In Southern parts of India (at least in Tamilnadu state), there are lots of rituals involving crows. It's very common to see people calling crows (giving the cawing sound) and feeding them food on Saturdays. It is also believed that when people die, their soul supposedly comes back to visit the family as a crow, hence they feed the crows especially on the death anniversaries of family members. When visitors come to your home, the crows often inform the residents well ahead by cawing in-front of the home. I used to make fun of my Mom for believing in all such random events, saying crows are just stupid birds habituated to getting fed by humans and don't remember anything. Now that I see that crows can be smarter, I could have been wrong.