I was really happy to get Gandalf the White as a prize for getting 2nd General (is that like 2nd breakfast?) at the Gathering, and I've been vaguely considering how to actually use him in a list. Well, my wife and I were watching The Two Towers tonight, and I had an idea hit me - what if I were to take all of my pre-existing notions of what makes a good army and just throw them out the window? Go with an entirely themed army with a completely different philosophy - mobile destruction!
So here is a random possibility - "Dawn of the Fifth Day"
Gandalf the White on Shadowfax
Erkenbrand on horse
Captain of Rohan with heavy armor, shield, and horse
4 mounted Rohan Royal Guard (3 w/throwing spears)
9 Riders of Rohan (4 can shoot bows)
1 Rider of Rohan with banner
Total models: 17
Total Might: 8
Bows: 4/14 29%
I have absolutely no idea if this list would work in the least, but damn I think it would be fun. Screw all this surrounding your opponent, outnumbering him and outmaneuvering him - this list is all about charge into the teeth of his line, blow the Horn of the Hammerhand, break through with a Heroic Combat and lay waste to his squishy bits! With a horse mounted Gandalf-bazooka! The only thing I'm really tempted to do is put in ANOTHER mounted Captain of Rohan instead of some riders.
This will require some thought...