Here are a few I found useful (and noticed that not everyone knows they are possible)
RCD310 radio signal stats
Hold MENU when in radio mode, and a signal status screen will be shown
Rain-closing roof
In the convenience-menu, the option " Rain closing" can be enabled by using VagCom. I'm not sure if it really closes my roof or windows when it starts raining, still testing...
Mirror-down
Your passenger-side mirror will dip to the sidewalk when you're reversing, depending on the configuration of your car.
Clothes-hanger
I feel ashamed to say this... but I haven't noticed it until my brother pointed me to the fact that there's a hook in the rear, that can be used to hang your clothes on... thanks bro!
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Climatronic codes
Hold AC and the "Blow some fresh air in my face" button to access the diagnostic menu of the airco-unit.
feel free to post your tips & tricks, please don't clutter this topic with other posts
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