I borrowed this off my sister because I have heard a lot of good things about it. It reminds me a lot of The Secret Diary of Adrian Mole, Aged 13 3/4 which was a best-seller in the early 80s. This story is a diary entry to the reader telling the life story of a 15-year-old boy who is a little different.
Like ClareBear I read this very quickly, I started it late last night and polished it off as soon as I got up this morning. I tried to stop and place my bookmark but I couldn't find a spot where my interest was lost. I recommend this book to anyone. It has a lot of late 90s pop culture references which gives you a bit of insight into how much the world has changed. Also a movie is coming out (starring Emma Watson and Mike from Friends), so have a look at the trailer - which I personally think looks pretty great.
ClareBear has beat me to reading this one, look at her summary!