Our family has a tradition of driving around to look at houses with outrageous Christmas lights. This year we made visit to: 1439 Joel Drive, Ft. Washington, PA 19002. This house has quite a number of animated displays. In fact, this is the 28th (and last year!) this family is doing their display. Check them out if you are in the area.
If you know of any fabulous light shows in the Philadelphia area feel free to post addresses as replies to this post.
Musings on Faith and Psychology 
Check out “Light up a Life” at 1320 Butler Pike, Ambler, PA 19002 (not far from the house on Joel Drive). You can see this unbelievable house when you drive past on 309. Here’s their website with more info – http://holiday.acteon.net
Another one is Maloney Lights, a house with lights synchronized to music, located at 644 Cypress Road, Warminster, PA 18974. Here is their website – http://www.maloneylights.com