Buy.com offers the SRS Labs iWow 3D Audio Enhancer for iPhone, iPod, or iPad for $29.99 with free shipping. (Amazon charges the same.) That's $4 under last month's mention and the lowest total price we could find by $20. This adapter purports to provide a enhanced "3D sound field" from all multimedia content. It features a 30-pin connector, headphone jack, one-button control, and SRS iWow app.