Omnivorous Surfer

I have registered (free, of course) for this one and have the number in my cell phone directory ready to use. I've tried it a couple of time and found it to be somewhat useful.

Get price comparisons while shopping using Frucall and your cell phone. You can call, send a text message, or use mobile web, if you have access on your phone or PDA, to send a product name or barcode to Frucall. You will receive in reply a list of vendors and their prices for the same item. It works online, too, and you can try it out on the website without registering. This uses Yahoo Shopping to generate the listing.

I registered a week or two ago, and my registration has not generated any junk email.