The Wish List by Eoin Colfer

I recently read Everlost by Neal Shusterman, but I didn't like it nearly as much as Unwind.  A much better stuck-in-limbo-between-life-and-death book is The Wish List.  A troubled teenage girl (sorry--I read a lot of teen lit) gets sent back to earth after death to basically make up for some bad decisions.  She ends up helping an old man achieve his life's wish list.  This book is by the guy who wrote the Artemis Fowl series, which is a smart fantasy/science fiction series for kids ages 10 to 100.