I have about a 2-3" diameter bundle of cables running down the back of my AV wrack. I'd like to wrap them all in some kind of a fabric-y cable wrap that looks a little better. Does anyone have any recommendations?

maybe something similar to this, but needs to fit a larger bundle of cables:
http://www.google.com/products/catalog?q=tech+flex+3%22&hl=en&client=firefox-a&hs=2cq&rls=org.mozilla:en-US:official&prmd=imvns&bav=on.2,or.r_gc.r_pw.,cf.osb&biw=1429&bih=988&um=1&ie=UTF-8&tbm=shop&cid=16230531328087016661&sa=X&ei=rAOmTs6aCa6rsALoo6CwDw&ved=0CG8Q8gIwAQ

David, that braided sleeving is expandable and comes in sizes more than big enough for your needs. You might browse this site to see if there's something that you like.

What, no duct tape?
Drilling holes in hockey pucks also makes for sturdy wraps and allows you to separate the cables by drilling multiple holes. Use Tim Horton's coffee cups temporarily until you get all the holes drilled in the pucks. Make sure you point all the coffee cups in the same direction, always downstream with the signal, to keep the sound flowing smoothly.

That was almost too detailed, Andrew. You really tried that didn't you?

Use colored duct tape, lol.

Ha. No, of course not! Mmmmmh, not exactly. Well, kind of.
OK, It's like this.

Many years ago, I was house & dog sitting for a friend. It was an older house and there were water pipes that rattled Very loudly the whole time when you had cold water running. After a couple of days, it was driving me crazy and I finally investigated down in the basement.

A cold water pipe running to a laundry room sink was run too close to another cold water pipe. It looked like it was added after the initial build and it was connected via a plumbed split right at the tank. I looked all around for something to shove in between them and couldn't even find an old rag. At some point I kicked an old hockey puck on the floor and had the idea.

I took it to my buddy's scroll saw and made a hole slightly off center with a slot to shove the pipe in through and also cut a pipe sized, half circle out of the other side. (I didn't think slotting two holes would leave it structurally sound enough not to split.)

With some tweaking at the scroll saw, it fit nicely on the pipes as a spacer and the annoying rattle was gone. It has to be 15 years ago and the puck is still there. I like to check now and then.

Final Note:
No paper cups involved. Although I probably had a Timmies before I started the job.