Godel, Escher, and Bach would be my top recommendation for a book club.
I've started this book countless time and have never completed it. This would be the firm kick in my rear necessary to finish it. (The same could be said for
Finnegan's Wake, listed above, which I'd also be happy to read along with the group.)
If we ever were to break off into the realm of short stories (or collections of short stories,) readings of Borges and Lovecraft could be exciting. In addition, I'd be interested in nominating
The Rings of Saturn (Sebald),
Death in Venice (Mann), and
Alice in Wonderland (perhaps in tandem with
GEB?) to the list.
"The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents." -lovecraft