Al Petrak correctly suggests great caution when donating to an
institution.  Libraries have been known to sell off donated collections
that they had received from donors who had given them precisely to
avoid a sale.  My wife's parents donated a painting they had owned for
years to a library.  The head librarian recognized it as a rare work,
illegally took it as his own, and sold it for a vast sum.

If one is truly wealthy, establishing the "John Q. Jones Collection of
Piano Rolls" or whatever, and then funding it in perpetuity, might be
in order, or perhaps creating a whole new museum.  "Mrs. Jack" Gardner
of Boston did that, with the stipulation that her house, the Isabella
Stewart Gardner Museum, be open to the public, and that _nothing_ in
the museum ever change.  If you see it today, you see it as Mrs. Gardner
saw it, except for the blank walls where about a dozen works were
stolen in 1990.  The trustees are not allowed to sell or loan out any
artworks or even to acquire new ones!  If any changes happen, the
museum reverts to some other dire situation of ownership while the
trustees are likely turned into toads.

Peter Neilson

 [ The web page says, "The Gardner Museum has remained essentially
 [ unchanged since its founder's death in 1924.  Unchanged but
 [ certainly not stagnant."  More at http://www.gardnermuseum.org/ 
 [ -- Robbie