Pull To Dismiss work as you would expect: there is a virtual keyboard on the screen, then you can be removed by wiping it down on your screen. In some situations this is already possible by tapping on the text field instance.
Pull To Dismiss was developed by Ryan Petrich, who also previously responsible for such RetinaPad Activator. Since only a single function tweak adds, there are no settings to change.
Pull To Dismiss is freely available via the BigBoss repository and requires iOS 3.2 or higher.