at which direction electric charges flow when you rub 2 things together?

They don't actually flow - the charges are actually being seperated.

Positive and negative charges pulled away from each other when things are rubbed together to cause static electricity.

These charges can be used to make a flowing current by "pumping" them into a capacitor then releasing them into a circuit. When closing the circuit, the current will from from negative to positive.

yo RJ!

The ancient Greeks discovered that electric charge could be transferred between two objects by rubbing them together, rubbing plastic and fur together results in electrons from the fur being rubbed off onto the plastic, leaving the fur positively charged and the plastic negatively charged. When glass and silk are rubbed together which one has the electrons rubbed off

erssguy is right. When you re introduce the 2 items back together, the positive and negative ions want to "look" for each other again and re-connect. I couldn't find any sites for you, but will keep trying as long as you have your question posted. Good luck!