Wikipedia:REWARDS
You may be looking for:
- Wikipedia:Barnstars - informal rewards given by one editor to another
- Wikipedia:Reward board (a.k.a. WP:REWARD) - informal rewards (including barnstars, exchanged labor, prizes, even cash) offered by one editor to others in exchange for on-Wikipedia work, such as advancing an article to Good Article status, providing a needed image of an article subject, finding a lost reference, etc.
- Wikipedia:Bounty board - essentially the same as the Reward board, except that the offerer makes a donation to the Wikimedia Foundation in exchange for your labor instead of offering a personal prize