A social networking website with petition system like [url removed, login to view] where you have to create a petition with Signature Goal: 50 people.
If you have some friends and good petition it is easy to find 50 friends and their friends to sign this petition
1-You can choose any subject of petition you like
2- No restriction on country, could your friends coming from any country.
3-No bots or spam
4-No fake sign in like emails + photos + proxy . (only 100 real human people)