An on-line game site involves a question engine coupled with a plurality of terminals controlled by respective players, for (i) sending predefined questions to the players, receiving answers to the questions from the players, and awarding prizes to the players over a given period of time as a function of the answers received, an activity measured by a traffic index representative of the number of players that have played the game over a given time interval, (ii) displaying, together with the questions sent to the players, paid-for advertising insertions, established on the base of a given rate, (iii) evaluating the receipts associated with the paid-for advertising insertions, (iv) establishing an endowment for the prizes to be awarded players over a given period of time, the endowment being a function of the level of the receipts, and (v) repeatedly increasing the endowment corresponding to an increase in the receipts resulting from an increase in the traffic index.