Possible Performance Upgrades?

I have a used A4 Quattro 3L from 2003. I believe its a B6, sorry if it's not. Under 90,000 miles on it, too. I've been searching google for things that I could do to it, but all I see are things for the 1.8T. What can I do or have done to it? Thanks guys.



Random pic of my baby.

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