Available for free on the Project Gutenberg site, with illustrations from the 1843 first edition: A Christmas Carol by Charles Dickens.
And, to make this post a little bit royal, here's a quote about Charles Dickens from Queen Victoria's diary: "He had a large loving mind and the strongest sympathy with the poorer classes. He felt sure a better feeling, and much greater union of classes, would take place in time. And I pray earnestly it may."