I made my own book hosting/reading website because I was tired of having my books scattered on different platforms, using different readers, and having problems syncing between devices.
My solution can run on any device that has a browser with HTML5 support. Everything is synchronized, so I can start reading on my pc, then jump to my tablet and continue from the same page. I can also find metadata and covers for my books automatically.
Everything is written in PHP with my own package based framework. The reason for choosing PHP is because the site can then run on cheap and lightweight hosting solutions. Right now I am running it alongside my website which both cost me a combined 3$ a month with extra resources left.