My projects on Yii:
Obolon promo (Obolon is most famous ukrainian beer brand).
Taft promo (Hair styling stuff from Henkel / Schwarzkopf)
On this promo-sites user registration is available, registration of promo-codes that is supplied inside production, chosing prizes (if you get lucky promo-code), delivery status of prizes.
Also sites with reports about promo-actions supplied for clients.