Outdoors are perfect for EL wire... they can be run off of AC or DC (low-volt batts tend not to electrocute you if they get wet).
Last year, I even tried incorporating the different colors into some experimental 3-D scenes (using both Red/Blue and Chromadepth glasses), but since I could still percieve the light source (i.e. the wire itself rather than its color), the effect was negated. Haven't given up though...
MT, are you following me around?