In Amber diceless roleplaying game players get extra points for building their characters by committing to player contributions, such as: Writing a diary, writing game reports, drawing character pictures as Trump cards.
In Amber diceless, players get points at character generation, which is problematic if they later find out they over-committed and can't keep up with their tasks, or are simply lazy.
Other examples might include writing a newsletter, bringing snacks, allowing people to play at your house.
Let me call out-of-game tasks that players do for in-game rewards with the name of player contributions.
What kind of player contributions have worked well, in what sort of games? Correspondingly, when do player contributions fail badly or fall flat?
By working well, I mean that it encourages players to do the task and not feel like they are doing unpleasant homework.
I am designing an old school adaptation/severe mutilation of Solar system (newer edition of the Shadow of Yesterday), where players get experience for triggering keys. I am going to only give experience once per session per key and intend to tie some of the keys to both out-of-game player contributions and fictional events.
For example: 1 xp when you draw dungeon maps during the session, 3 xp when your character makes them publicly available in the fiction and you, the player, make the maps publicly available to all the players.
Please note that the question is subjective (but hopefully not argumentative). As responses, please give personal experiences or cite some other credible source. In particular, I am not interested in "My favourite game also has player contributions! Check it out.", but I am interested in "Here's an actual play report that touches on the issue of player contributions. I found it helpful because of these reasons."