While perusing this preview (http://www.edmunds.com/reviews/roadtests/firstdrive/86970/article.html?tid=edmunds.h..reviews..3.*) of the new Audi S4 on edmunds.com, I noticed a brief mention regarding back seat space that might interest users of this message board:
the S4's major faux pas is endemic to the entire A4 lineup, namely the paucity of rear seat room. Now that virtually all Japanese sedans have spacious rear accommodations, and most European competitors have at least paid passing attention to the needs of those relegated to the back, the S4's lack of rear legroom is glaring. Hell, even the recently released four-door RX-8 is generous in comparison.

More room than an S4? Works for me... :)

-ss

I have sat in my friend's 2002 A4, and I was plenty happy with the rear space room.. if it's close to that, I'm a happy camper!

I've sat in my cousin's 2000 A4, and the rear seat space (esp. leg room) is much tighter than my Protege.

The Protege definately has an amazing amount of room in the backseat for a car of that size.