Tascam CD-BT1MKII Portable CD Bass Trainer
Unit + AC adapter. Works great. Slows down CDs to 1/2 speed without dropping the pitch an octave. But you can still fine tune the pitch to your instrument. Also has a bass enhancer.
I've learned a lot of songs with this unit.
$50 shipped USPS priority mail (around 2 day delivery) and paypal'ed.