Well, there is SBSettings or NC Settings (both free) - these will allow you to turn on/off WiFi.
Or, if you have Activator installed (another free tweak), you can set up an action to take you directly to the WiFi part of your Settings app.
Off the top of my head, I can't think of anything else that might do the trick. Maybe someone else will come along who knows of one...
Marilyn