Have you flipped up the cover on the sun-visor mirror yet?
While you're there, have you noticed the little mini sun-visor to cover the bit behind the mirror?
Have you opened the back doors and noticed that only the courtesy light on that side comes on?
Let's face it, a Lexus ain't just an executive car, it's an executive toy!
Why not get a "flat" key cut? I take it you only really want a spare in case you lock the other one inside?