If you want a 4 Gb black nano right now for $199, try your nearest Microcenter. They made a price mistake in their latest flyer and put $199 instead of $249, but they're still honoring the price until the stock runs out in stores. There's a limit of one per customer and there're reports that they'll actually ship them to you if you call them and pay for shipping to your state/city.
Slickdeals.net (as well as FatWallet) has a thread with a scan of the ad and me people succeeded in price-matching in Circuit City and Best Buy, but it really depends on the cashier/manager.
That's about as hot of a deal as you can get on a spanking new Nano.