Sometimes, after a brief nod at work, I become more aware of where I am and demand, "the day...what day is it man!" Usually this gets my coworkers scurrying, like they don't have enough to be concerned about anyway. The point, though, is that sometimes I can't be sure if I'm in the past, the present or the future.
Reading this thread, I get the feeling that I've been here before. On the other hand, if you've already read what I've just written, sorry for the redundancy. Anyway...
Is Gandalf's staff wooden? As mentioned, he uses it to set other wood afire.
Though I might disagree with equating a cross/Crucifix with a wizard's staff, I like the analogy presented by
Roa_Aoife. Think that this was done well in the movie "Salem's Lot," though I may be mistaken. The main vampire confronts a priest who is armed with a Crucifix, but easily overwhelms the holy man as the vampire knows that the priest has no faith in the artifact, therefore it has no power. The main characters fashion crosses out of tongue depressors, and these are much more effective against the blood-drinking undead. But in regards to the staves of the Istari, I don't think that it is their faith in the item that gives any benefit.
Regarding Saruman's staff: This token of office did not aid him when he addressed Theoden and Gandalf, and its breaking only showed the mastery of Gandalf and the feebleness of Saruman. Plus, as a symbol of Saruman's office, it was taken from him as he had gone over to the enemy. Saruman, like many others on that side (Melkor, Sauron) lose their innate power by dispersing it amongst others to control these others. Sauron had to give some of himself to create the Ring to control the other Rings, so much so that he would be destroyed when it was. Saruman, in order to control his orcs and hillmen and Wormtongue, gave away the power that one such as Gandalf retained. So my point here is that Saruman was no more or less powerful with his staff, and so it cannot be a great channeler (i.e. no multiplier effect). And I don't think that the staves have any power within themselves, or surely Sauron would have tried to take them. Gandalf may use the staff to effect something - start a fire with the end of it - but it's not the staff, but Gandalf. Can't see him shooting fire out of his fingers, or breaking the Bridge with his heel, and so he needs some tool.
Gandalf, like the other Istari, came to Middle Earth as an old man. These staff-men were forbidden to declare themselves, matching power with power with Sauron, and I would think that the purpose of the staves that these men carried was to
remind them of that. A old man walking with a staff is not too unlikely, and so the symbol of their office was more ordinary than would be a rod or some flagrant banner. And not only were the Istari hobbled so that the Free Folk of ME would have to
act to remove the scourge of Sauron (and not sit back and have the wizards do it for them), but also it afforded them a disguise that, for a while, may have hidden them from Sauron and also permitted them to interact with the peoples of ME who would be less intimidated by these old men who needed a 'third leg' for support. So the staff was a reminder of the Valar's decree and a camoflagued symbol of office.
A few posters have already noted that Gandalf's staff breaks on the Bridge. All seem to think that Gandalf breaks it, or at least shoots so much energy through it that it gets overloaded. But consider, when Gandalf first meets the Balrog, though at that time he does not know what it is, he tries to shut the Mazarbul chamber back door to slow the pursuit of the orcs and this other. The Balrog counters his spell, and so Gandalf whips out one of those Words of Command and shatters the door.
Note that the door breaks but Gandalf's staff is intact. Also, remember, Gandalf is aware somehow of this other, and knows that this other has 'preceived' him too. There's some mental stuff going on, obviously.
So consider: Just a little while later Gandalf decides to hold off the Balrog while the other eight escape. Winged or not, presumably if Gandalf breaks the Bridge, the Balrog is stuck as Gandalf has either cut off the pursuit (orcs AND Balrog) or at least slowed it somewhat until some other fortunate accident comes up ("Anyone see any Eagles?"). The Balrog, no dunce, knows that it would be better to continue the pursuit while Gandalf is still drained and that it might be better to take on the Nine Walkers inside of Moria than outside. It guesses what Gandalf is attempting after its sword is broken, and so it goes for the counterspell again. The strain on Gandalf's staff, which is being used to direct his spell to crack the bridge, is just too much. And so this is technically a power overload, it's not Gandalf's power alone but that of the Balrog's too.
So the Balrog is mostly responsible for breaking Gandalf's staff, as later Gandalf will be when Saruman's is broken.
And what does PJ add to this? Well, that's a really shallow puddle, to be sure.
**Special prediction - The Steelers will win the Super Bowl in 2006. Place your bets early
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