I want to add to what Braiam has said. Stack Exchange has the following badges as reward for sharing a link with your networks:
- Announcer (Bronze):
Shared a link to a question that was visited by 25 unique IP addresses. - Booster (Silver):
Shared a link to a question that was visited by 300 unique IP addresses. - Publicist (Gold):
Shared a link to a question that was visited by 1000 unique IP addresses.
If you are after more information those badges are specified on the badges section.
