Barcodes in the news

Way back before there were many laser printers I wrote a piece of software (for fun!) to print out barcodes on a dot matrix printer. Ever since then I've been somewhat interested in barcodes, I guess it's the idea of organizing my life.
Some recent links:

• Somebody decided to make barcodes more beautiful.
• Here's there's a free, community based database of barcodes (barecodepedia) If I write a program to keep track of groceries (or whatever) I'd put and get the information from here.
• I've been looking to print out barcodes and slashdot people appear to recommend kbarcode for linux.

My idea is to have a book of barcodes for commands. Use cases:

• Add a book
  

1. Scan "My library" barcode found in book, to put the program in that mode.
2. Scan "Add Book" barcode to put the program in a mode to add a book that's in my library.
3. Scan the book's ISBN and
4. Check if the ISBM is already in my library, if not
5. Get book information from Amazon.com

• Checkout a book

1. Scan "My Library" again from the book of barcodes which I print out.
   
2. Scan "Checkout"
3. Scan the book's ISBN, verify that the book's there.
   
4. Scan the person's barcode.
5. Show that the books has been checked out by so and so.

• Add groceries

1. Scan "Groceries" barcode
2. Scan the store where you bought the groceries
3. Scan an item
4. If found in my database or on a public database then show the item.
5. If not found ask for the name/size etc. of the item.
6. In either case show the most recent price and ask to confirm (or user put's in a new price by looking at their receipt).

I suppose keeping track of my stuff for insurance purposes would be nice as well.
Unfortunately, there aren't enough useful things for me to use a barcode for, and they cost money. Also, I'd have to write all these programs which takes a while.