Halting State (Charles Stross)

This is also a re-read of a past favorite (I'm in comfort-book mode, I guess, as the semester is winding down). It's a mind-boggling trip through the virtual realities of near-future Scotland, opening with a bank in the online world being robbed by a party of Orcs and a dragon and going sideways from there. The story is action-packed and the mystery is gripping, as it explores how the digital world has changed us fundamentally (one character, looking around Edinburgh, notes that it looks pretty much as it has looked for about a hundred years, but underneath the stone and glass all the nerves and muscles that make things work have been ripped out and completely replaced). I enjoyed it.