ePub sounds fancy, bleeding edge even, doesn't it? Who ever knew it was just a bunch of XHTML and CSS in a Zip archive?
Well, that's all it is. If you'd like a sample ePub I marked up using vi (yes, the UNIX text editor!) and some old data about 19th century Prussian military units stationed in Potsdam, help yourself! It's hosted using Amazon S3, so availability shouldn't be an issue.