Over the past several days we've been reviewing the insurance coverage we have for our home, cars, life ("lives"?), etc. A few years ago we added a "rider" to our homeowner's policy expressly to cover my tools. Without the rider our basic policy capped tool coverage at something like $500 which is obviously not adequate for a woodworking shop. So our tool rider covers us for full replacement costs up to $25,000 which should be enough to get the vast majority (if not all) of my shop tools. The rider only adds $27 to our yearly insurance bill, so it seems like a great bargain for the peace of mind it provides.
The other nice thing about our tool rider is it forced me to make/update a tool inventory including pictures of each major tool. We track serial numbers, purchase prices, make/model, etc. All this is kept on line (partly on my website) for safe keeping.
With this we feel pretty good about insurance on our tools and shop. Hopefully we never need it, but it's nice to know that we're adequately covered if it's ever necessary.