Walmart offers the HTC Wildfire S No-Contract Google Android Smartphone for Virgin Mobile for $99.88. Shipping adds $2.97, or choose Site-to-Store pickup.
Even with shipping, that's $53 under our January mention and the lowest total price we could find for any carrier by $26. Sales tax is added where applicable. It features a 3.2" 320x480 color touchscreen, 600MHz processor, 512MB RAM, 5-megapixel digital camera, WiFi, Bluetooth 3.0, microSD card slot (2GB card included), Android OS 2.3, and more.
Update: A reader notes that Virgin Mobile direct offers it for $99.99 with free shipping. (It's the eighth phone down the page.)