Nathan brings up a good point. Is everyone insured?Everybody with large collections should get them insured.
Nothing sucks more than having a large amount of CDs stolen or lost and having to pay for their replacements out of your own pocket. I'm sure this has happened at one time or another to most of you.
Correct me if I'm wrong, but either homeowner's or renter's insurance should cover your collection, whether it is in your house or not. A book of CDs stolen out of your car will NOT be covered by car insurance.
Tip: Make sure you keep a detailed list of your collection. If stolen, many insurance companies will offer some flat amount per CD (like $12), but if you can provide them with the specific list and even better accompanied by online sources with prices, they might be willing to cover the full amount (many CDs we buy cost more than the flat rate they offer).
I had this exact thing happen when the CD player in my car was stolen, and I had to get the 12 CDs that were in it replaced. They were only covered by my car insurance because they were in a bolted-down piece of electronics in the car. If they'd been loose in cases, they wouldn't have been covered. I was offered $12/CD, but since a few were imports (up to $30/CD in some cases), I provided them the list of CDs with online price references. They either tracked them down and bought them for me or gave me the money to buy the rest myself.
Granted the insurance is only really worth it if a lot of CDs get stolen as you'll more than likely have to pay a deductable, which could range from hundreds to over a thousand dollars depending on your plan.
Be prepared!
Jesse