LockAlert is a new jailbreak tweak that allows you to easily close a push notification preview straight on your iPhone's lockscreen. Instead of having to slide to unlock your iPhone, the notification can be dismissed by tapping an "X" that LockAlert adds to the top corner of the preview dialog.
If you aren't using a replacement system of notifications, like MobileNotifier, on your jailbroken iPhone, LockAlert could be the perfect addition to the iOS method of push notifications.