But here is probably the most expensive iPod accessory, and definitely the most expensive speakers being marketed for iPods. The most expensive iPod speakers are Hammacher Schlemmer Studio-Quality Triode-Tube iPod Speakers.
From the product website:
This is the first tube-based iPod® speaker system, producing a luxurious warmth and clarity prized by audiophiles and previously difficult to reproduce outside of custom-built amplifiers of a handful of live musicians.
Developed and built by German audio technicians, the system consists of an aluminum-encased amplifier housing four powerful Class-A tubes which glow gently as they generate warm, low-octave sound that is virtually distortion-free, considered by audiophiles to be the most pleasing to the human ear. The tube amplifier smooths over distortions found in modern digital recordings while helping to compensate and minimize the quality loss inherent in compressed audio such as MP3s. The matching double-cone, full-range speakers—designed solely for use with this system—faithfully generate warm, realistic tones using a single, highly synchronized chassis per speaker (reducing ill-timed and out of phase audio).The set of speakers will only put you back a mere $3,999.95.