Cecelia Ahern wrote PS I Love You.. and this book too: Girl In The Mirror.
It's composed of two short stories and more importantly is preluded by the following paragraph, that sets the scene for the stories that you are about to read.
"There's no use trying, one can't believe impossible things"- Alice (in Wonderland)
"I daresay you haven't had much practice," said the Queen. "When I was younger I did it for half hour a day. Why, sometimes I believed as many as six impossible things before breakfast,". And so the author asks you to believe in the impossible, and is followed by two impossible stories.
The first is Girl in the Mirror: a story of a woman who lives in the mirror and steals people's lives or their eyes. I didn't like this story very much, unless there was a hidden meaning to it somewhere.
The second is called The Memory Maker: this is a story of a man who has invented a machine that can change the most important memories, alter regrets. The underlying theme of the story is, everyone deserves the opportunity to erase regretfull memories. This was a very touching story, written sparsely.
The book retails at Rs 199 at stores, but you can get it discounted at Flipkart.com :)