If you've been considering signing up for Vonage VoIP service anyway, why not do it at Circuit City? Starting on Black Friday, the electronics retailer is offering a $200 shopping spree to customers who sign up for one year of Vonage. Of course, you must use the credit on items offered at Circuit City, but 200 bucks can go a long way toward certain gadgets. Take MP3 players, for example. Circuit City carries about 50 devices for less than $200, including top models from brands such as Apple, Sony, Creative, Samsung, and SanDisk. You might even have some dough left over to put toward a handy accessory.