Best Portable Sound

Definitely the ipod. I have the 15 GB version, which is slightly thinner and lighter than the 20 and 30 and holds 3500 songs. Nice sounding headphones and can be hooked up to a radio/stereo at a friends house, the office, etc.

Ipod is cool, but it is not good for classical as it is compressed.

With a 777 or old "portable" CD, a Grado phone, or a HD580/600 with a small amp, you can get superb sound which MP3 no way to compare.

iPod is not limited to compressed formats. Uncompressed, the 15 GB version will store approximately 12 full albums. Looking for input from someone who has ACTUALLY COMPARED sound quality iPod, minidisc and / or CDP. Thanks in advance for any info.

I have a Sony MiniDisc player (MZR500) and also a RIO Volt.
Either will do compressed or noncompressed.
The mini-disc with 80 minute discs using the 2X ATRAC (160 minutes) compression is a higher quality than MP3 or WMA at even high bit rates (+128)IMHO.
You do not have to use this option, however.
The 2x option on minidisc is also almost indistinguishable from CD's.
I do have decent headphones (K0SS 35's) and would highly recommend a mini-disc player over any portable format out there. The size and sound quality are great.

I have heard the hard drive based players and for pure storage they are great, but size is generally bigger.