For a digital equivalent, I quite like openlibrary.org It's got a similarly chaotic vibe (partly because they've not totally normalized their metadata yet) and lots of obscure stuff.
One particularly weird benefit is searching for your fave author and finding some PhD or other obscure fan produced work about the author (and/or their works) that would never make it into an actual bookshop, even a digital one.
They have some digital experiments to recreate the browsing a library feeling too (similar to the rash of Mac book cataloging apps that appeared on the Mac way back and may have kicked off the most recent revival of the skeumorphic design trend.)
One particularly weird benefit is searching for your fave author and finding some PhD or other obscure fan produced work about the author (and/or their works) that would never make it into an actual bookshop, even a digital one.
They have some digital experiments to recreate the browsing a library feeling too (similar to the rash of Mac book cataloging apps that appeared on the Mac way back and may have kicked off the most recent revival of the skeumorphic design trend.)