Knowledge of Angels.
To be honest, my heart sank a little when I received this; it looked like something more akin to a Dan Brown than I would normally read, but it was shortlisted for a Booker, so I persisted because I'm a snob. I was however surprised. It was relatively well written and I think based on some interesting ideas. The author clearly has an interest in philosophy of religion, linguistics and psychology (as do I). I think at times some of these ideas where portrayed a little clumsily (e.g., more substance over style), but all in all, quite nicely done. I felt the book faded towards the end, but it kept me going to that point.