I'm not much of a bookie... I don't find fiction pieces that hold my attention very often. Tinkers is doing it though. I've been reading out-there stuff about sacred geometry and whatnot... Drunvalo Melchizedek's "Ancient Secret Of The Flower Of Life" is an excellent book, but it's definitely not for everyone. Some would consider it fiction I suppose, heh.
What I like about Tinkers is he takes his time to describe things that other authors would not, and effectively evokes strong emotional responses to things that would seem almost benign or irrelevant if it weren't for the way he chooses to frame and note them. Might not be for everyone, but I find it really captivating. It also explores interesting subject matter, like explaining how old clocks are repaired and really making me appreciate the difficult and meticulous nature of the work involved.
Oh, Rob Brezsny's "The Televisionary Oracle" is fucking amazing tripped out quasi fiction. You can tell the dude had a whole head full of acid when he wrote it. in a good way.