After extensive research based upon classified information from deep within Apple (and at the expense of several human lives, regrettably), Low End Mac published a never before seen list of iPods that never quite made out of the R&D labs and into production.
Some of the less fortunate models:
iPod wristwatch: This iPod comes with a built-in wrist band and has one more menu item: Wristwatch Display.
iPhone iPod: This variant of the iPhone has a docking station in it for the iPod nano.
StereoPods: Two iPods, miniaturized to the size of hearing aids, synchronized via Bluetooth to play one channel (each) for about seventeen seconds.
iPodPlasma: A 110-inch plasma screen TV with a built-in, non-removable iPod.
StevePod: Steve Jobs' iPod with 2 TB storage capacity with a small video projector for a screen; available 3Q 2017.
SegPod: A Segway with a built-in iPod.
Podway: An iPod with a built-in Segway.
PeaPod: An iPod delivered in a cute floral arrangement.
aPlod: An iPod for actors.
Operation Enduring iPod: a sandproof, bulletproof, satellite enabled iPod. Cost: $23 million.
embeddiPod: Subcutaneous iPod. You heard it here first.
Thomas the Tank Pod: Thomas needs to deliver a musical interlude to Sir Topham Hatt! Can he figure out the menus in time?
Walt Disney's Brother Pod: Sold in pairs, one classic and one nano, targeted at bears that happen to be different sizes but brothers.
The digital music landscape might be completely different had these units gotten the thumbs up from CEO Jobs.