Sonoma Wire Works GuitarJack (photos)
GuitarJack ($199) is an accessory for the iPhone and iPod Touch that allows musicians to record their instruments directly, using compatible recording apps, such as Four Track.
As iPhone accessories go, the GuitarJack is a little bulky, but it packs an impressive number of high-quality audio connections and controls.
The right side of the GuitarJack offers a full-size 1/4-inch instrument jack; the left side includes minijack headphone output and stereo line input. Each input has 60dB of continuous level control.
The 30-pin connector of the Guitar Jack is compatible only with iPod Touch (second and third generation), iPhone 3GS, and iPhone 3G.