How can I add a card in a private board (with a group of people) that only me can see ?

[Pierre Vasseur]

I would like to add a card that only me can see in a board with multiple people, is that possible with the free version of Trello ?

[Matthew N]

 With Trello, permissions are board specific. At this time, Trello is not able to offer card specific permissions. This is a feature request that has been received, so hopefully this can be implemented in the near future. For the time being, you'll need to have separate boards for privacy.