I can do w/o:
Interior:
Navigation. I would never pay up to $2K for this option -- when I can still read a Rand McNally for $5. Yahoo Maps and Mapquest = FREE. (PS -- I don't have an ipod or Sat Radio either

)
Auto Temp Control: I've never had it, but have been in cars with it. I'd rather be in control -- and run my AC or Heat only when necessary.
If we are talking "aftermarket accessories, my list is very long
