I've build in an old wah-pedal inside a normal stompbox. This way, U can't control the wah with your foot, only with the finger-knob.
It equals the sound when leaving a wah-pedal in a constant frequency, just like the Dunlop Q-zone.
If you add an EQ-pedal, U can make sounds like playin' inside a beer-can or likewise.
Otherwise, there isn't that much you can do with the wah-sound, tricks I meen.