In 1934 the pulp magazine Amazing Stories published a serialized science fiction novel called Triplanetary by E. E. Smith. It is an action-packed space opera with lots of spaceships, battles, weapons and wild galactic sci-fi ideas.
Project Gutenberg has made the entire novel available in HTML and plain text versions for free download. You can also get the illustrations that went with the novel.
This is one of those surprising finds that make the Web so completely cool.
Here's the link to the images.