[Kalimac]

I'm in the camp that thinks he didn't know what it was. As Finwe points out, very few people knew what palantiri were; not knowing about it didn't mean that Grima was stupid. And while it was important to Saruman, I doubt that he let *anyone* know that he had it, let alone what it did (remember, in the book of FOTR, he doesn't even let Gandalf know - a fellow Istari who, Saruman thinks, is completely at his mercy at that moment). Spreading that kind of information to anyone would be insane; it lets them know how to damage you. And Wormtongue, while an important spy in Rohan, is not exactly Saruman's equal, nor does Saruman consider him so. I doubt whether Wormtongue had ever been permitted into the same room as the palantir until the siege of Orthanc turned everything upside down.

That's probably the only reason he was able to see it - Saruman was distracted and fearful, and when Wormtongue swam up to the gates probably wasn't as cautious as he had been earlier. It was probably a matter of "Just sit here while I think of something to do" and the reason that the palantir was still in a remotely accessible place was that Saruman had been trying to use it and hadn't had time to put it away before more pressing matters came up.

So in short, Wormtongue probably just saw this nice, solid round rock, thought that it would make a good missile, and threw it. I can't believe that he knew how he was damaging Saruman by it (as nice as it is to think of Wormtongue winning one for Eowyn [img]smilies/smile.gif[/img]) simply because while in Orthanc he was entirely at Saruman's mercy and would have been taking a huge chance by throwing out his greatest treasure that way. He could easily have been killed, and physical courage is definitely not among Wormtongue's virtues. Even when he gets up the strength to kill, it's always from behind.