@Robby:
Tom Baker would have made an exceedingly interesting Gandalf as well. I don't know how far or how seriously he was considered, but I know he was up for the role… though didn't want to spend the year and a half away from home. So he did Dungeons and Dragons instead. Sigh.
I don't know about Baker…he's got a great voice for it, I guess. He'd have to drop some weight. At least they got the seventh Doctor for Radagast, though. ;) I'm glad McKellan got the part, I don't think anyone would have done a better job than him.
There's also the story that they had a different Aaragorn first, didn't like him, and then Viggo Mortesson had like 2 hours to decide if he wanted the part and flew out, without knowing anything about it.
Yeah, Stuart Townsend. I remember when he was cast, and then dumped. PJ decided he was too young, which he was. Apparently he really wanted Daniel Day Lewis, but he kept turning it down. He would have been good as well.
Wait, this isn't the Tolkien thread, is it? :)