Groqit helps you keep track of what you own, and avoid buying it twice, by simply reading the barcodes on items you own.
You can use a Groqit without a computer. Just read the barcodes on items you own and take the Groqit with you. It will tell you when you wand a barcode in a store whether or not it has it already in your own inventory.
As a Groqit owner you can use the groqit.com website to translate barcodes, lookup items by author or title and store a backup copy of your personal inventory online (just in case) for free.
The Groqit is avilable from the groqit.com website for $95.