My user name is musically derived. Guitar strings are steel (although some of the varieties I use have nylon cores), harmonica reeds are brass, and both instruments (usually) have wood bodies. It could have been "steel, brass, wood, plastic, various composites, copper wiring, electronics and more" but that exceeded the character limit for usernames.
You are more than welcome to comment here, either to agree or disagree with what I am saying, but please keep in mind that you are having a conversation with me in my space. If your comment is something that, if said in conversation, would generate an "Excuse me?" reaction, I am most likely to delete it.
Additionally, you don't have to have an LJ account to post here, but I don't have conversations with strangers who don't bother to introduce themselves. If you don't want to post your introduction publicly, do it in a separate post which I will not unscreen. However, I generally do not unscreen anonymous posts in my personal journal unless I know the source.