Please Recommend Audiophile Solo Piano Recordings

One good option is to find labels where the house sound is of high quality (or at least one you like) -- that way you have lots of choices

Two that come to mind that I like are

1) Steinway, for example Bach on a Steinway
2) Hyperion, for example Angela Hewitt

Or for a more audiophile minimalist option Ito Ema Goldberg Variations on M*A recordings

Thank you all so far. Btw my preferred format is digital download.

One of the all time best in the jazz category, and any jazz fan knows it, is Herbie Hancock Piano. Prepare to be blown away. sbank above suggested Brad Mehldau which is another excellent recommendation in the jazz category.

Although a couple of these have already been mentioned, they're among my favorite solo piano recordings:

Jazz:  Bill Evans - "The Solo Sessions, Vol. 1" (on vinyl) probably my favorite for relaxing life-like piano
+1 for Herbie Hancock, Piano
Michel Camilo - "Solo"

Classical: Mieczyslaw Horszowski - "Piano Sonatas" (well recorded CD)
Frederic Chopin -  "Complete Nocturnes & Impromptus" CD  

Doubt it's on download, but the VAI CDs of Moravec playing Chopin (originally Connoisseur Society recordings) are uniformly excellent, sonically and artistically.  I'll also second the Nojima recordings mentioned above by Newbee.