I use a Boss ME-33 digital fx pedal that has wah wah but it was never was as good as a real CryBaby wah so I eventually cracked and got one of those and just run it into my digital fx. Sure I have to carry an extra pedal around with me but it's worth it. I originally was hoping the digital wah would do the job but I gave up on it.
The other advantage of doing this is the CryBaby has a metal construction and is much more solid under foot than the plastic pedal on my ME-33.
[This message has been edited by Nigel (edited 08-26-2007).]