I'm contemplating getting an A4 (B7), and I cycle alot so will need a good bike rack. Preferably, I'd like one for the back of the car. I saw one on Bird Automotive. I'd be curious as to what you all have for hauling bikes with your A4s.

with 2 viper fork mounts. Back of the car is only going to scratch it up unless you install a hitch.

You sure you want the rack on the back of the car? In my experience, the rear racks are awkward to attach and hold the bikes poorly. Multiple bikes tend to hit each other (and your car!) back there, and you also won't get into the trunk (I'm assuming you have a sedan...I've got an Avant). In any case, you can't go wrong with Thule...the Thule website does a great job in showing you what you need to buy. Yakima is also very good, and I'd trust my bikes on them. You want a beefy rack, even more so when you're loading up a heavier bike.

Also keep in mind that the "locks" on these are quite minimal, so you need to really think twice about leaving your bike unattended. The advantage to the roof racks is that they are harder to get at without people noticing...but, also harder to get the bikes out. I have no problems getting my bikes on/off the roof, but my wife (at 5'6") is too short and lacking strength. This may or may not be an issue for you. Personally, I like the looks of roof-racks...the rear-racks, well... not so much.

... for surf boards.

Thanks all for your comments.
I was actually thinking of putting a hitch on the car, but I'll also take a look at the Yakima and Thule offerings for the roof mounts.

I'v owned numerous Thule system racks and have loved them all. Very sturdy and interchangeability.

I prefer the roof option, but hitch racks are extremely easy to use. If you are going to put a hitch on the car anyway, and don't need to carry bikes at the same time you are towing something, then a hitch rack is definitely for you.

Hitch is cheaper, but less secure and all they do is shake back and forth as you drive off into the sunset.

Go for the roof mount.. don't be cheap. If you want a 44" Yakima fairing, I can see you mine. MSRP $55, but it will work for sedans.