MP3 recordings can provide unusually realistic playback, if made the
right way. You wouldn't believe the degree of "you are there" feeling
you'd get from playing a free download --- unless you actually visit a
certain website and do it. The site address, and an explanation of the
science behind all this, are in an article that just go printed (August
2005) in a music and equipment review magazine, "The Audiophile Voice,"
Vol. 11, Number 1. (If you subscribe, ask to start with that issue,
that has Janis Joplin on the cover.) Info available at

http://audiophilevoice.com/

Generally, the secret of super-realism seems to be that some recordings
(like those downloadable from the URL in the article) happened to be
close-miked and then MP3-encoded at 160 kbps. However, you could
probably do some of this yourself, if you have decent equipment and
carefully read the article. (Also, the reviewers in the "T.A.V."
magazine often describe other super-realistic recordings, available on
specific CDs, when they use them to test loudspeakers, etc.)