"Drinks or info chummer, both cost. One costs cred and the other costs favors. Too much of the former will give you a killer hangover, and too much of the latter might just kill you altogether."
A bartender contact/info broker for the Shadowrun rpg setting, can be easily adapted to any cyberpunk or other high tech campaign.
Surnames: The Chinese were among the very first cultures to adopt the use of hereditary surnames (around 2800 BC). But the custom didn't quite catch on in Europe - at least not until the Venetian aristocracy made it popular sometime between the 10th and 11th centuries AD. What culture made it popular in your setting and why?