Eric Lease Morgan has created a simple and traditional library catalog of about 300,000 items using the MyLibrary software. From the about page:
This is an index of just less than 300,000 MARC records -- a
traditional library catalog. MARC records were downloaded from
the Library of Congress. MARC data was cross-walked to MyLibrary
(Dublin Core) fields and imported. The content of the MyLibrary
database was indexed with Kinosearch and made accessible via an
SRU interface. Search results sport cover art from Amazon.com. If
reviews exist, then they can be read. Users can to view the full
MARC records in tagged, MARCXML, and MODS formats. Users can
create accounts for themselves and have items (virtually)
delivered to them.
The implementation is not necessarily intended to be a production service but rather exists to demonstrate what can be done with MyLibrary -- an open source digital library framework & toolbox.