Displays all your Facebook friends in a javascript dialog box and allows to select a friend and bind an action to that friend.
If user is already logged in, the index file automatically opens Facebook friend selector dialog.
Currently only selecting one friend is supported, in a future release selecting multiple friends will also be implemented.
I used it to post to a friend's wall, so you can use the javascript feed dialog (https://developers.facebook.com/docs/reference/dialogs/feed/) for that and define the "to" property with the selected id (inside the "function process(id)" in index.html).
GitHub Project Page: http://hbokmann.github.com/Facebook-friend-selector-dialog