Add yourself as card member (if there are no other card members) when adding to or dropping it on a list that you are a member of (in Pintask, the hackable task tracker).
This versatile plugin is only a couple lines of code:
if !Cards
throw "Hey, where are my Cards?"
if !Lists
throw "Look, I need those Lists, too!"
Cards.before.insert (userId, card) ->
list = Lists.findOne(card.listId)
if userId in list.memberIds and not card.memberIds.length
card.memberIds.push(userId)
Cards.before.update (userId, card, fieldNames, modifier, options) ->
if modifier.$set?.listId
list = Lists.findOne(modifier.$set.listId)
if userId in list.memberIds and not card.memberIds.length
if not modifier.$addToSet?.memberIds # don't add yourself when adding another member
modifier.$addToSet = {memberIds: userId}
This plugin is written in CoffeeScript. Plain old JS version is available, too.
So easy to make your own plugin ;)