Humble Bundle has monthly book and game bundles; you pay what you want to get a set of ebooks on a theme or mobile games or computer games and the theme changes each month or so (it might be every two weeks).
I have bought many bundles of ebooks and one of phone games and one of computer games and been satisfied.
They currently have a pretty cool bundle of books and software to help you paint. I am not sure but I think the programs are Windows specific. In addition to Bob Ross ebooks on how to paint, there are a few programs -Corel Painter Essentials 6 and some addition stand out - and even some art-themed games. I will buy this bundle. The minimum price is $15 (US) so it seems like a good entry point if you are interested in learning or playing around.
Bob Ross is more popular now as a meme than he was as a late-night weirdo drawing his 'happy trees' that no one watched. Now he is cool.