Not so sure about the start up chime. I used to like it, but have gotten used to it not making sounds. Since I use my Mac at work and arrive a little late, people always hear when I turned on my Mac.
You can turn it off in System Preferences --> Sound --> Play sound on startup
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If I'm remembering correctly, the startup chime will be silenced if you mute your computer before you shut down (as long as Apple carries this capability into BS).
You can turn it off in System Preferences --> Sound --> Play sound on startup