We recently reviewed the insurance coverage on our house and realized that we hadn't done an inventory in over 10 years. Our insurance agent recommended that we take pictures or a video of the house's fixtures and contents, then make a few copies to put away in safe places.
To do it, I just wandered through the house and took shots of everything - opening every drawer, closet and bin, and turning over silver and dinner plates to capture the patterns. My agent encouraged me to include jewelry, suits, scarves, ties and even clothes in winter storage closets. I also hit the attic, basement and outside decks for grills and furniture. Needless to say, many of the shots weren't high art and all of the rooms were certainly not particularly clean, but I was pretty happy with the result of only an hour or two of effort.
When done, I used a soft cover template in iPhoto with 16 pictures on each page and had the software auto fill it. It was loosely organized by room and I left some open white spaces to write notes just in case I wanted to add things in the future.
It cost about $20 to print the book, but I also made a PDF copy to store electronically on Dropbox and to send to my parents.