This is my second time reading the series. Basically, it's a graphic novel about the Holocaust where the Jews are mice, the Nazis are cats, etc. It won a Pulitzer and is an amazing story told in a really creative way. I picked it up again for my book club this month, and I've fallen in love all over again.
Re: WIFJR: Maus by Art Spiegelman
There is a book about these books (making of, thought process etc) that is really great, although I have no idea what it is called.
Edited to add: It's called MetaMaus.