A web scraper/document converter that outputs to e-book readers.
This is a project I created back in 2006/7 when I got an early Sony e-book reader. It was quite popular at the time, but after I sold my reader it stagnated. Kovid Goyal encouraged me to implement it in Python instead of C# to make it cross-platform, but at the time I didn't know Python. So he went ahead and made his own, web2disk, which gradually evolved into the now well known Calibre (https://calibre-ebook.com/) which is awesome and I use a lot.
More about this:
http://www.mobileread.com/forums/showthread.php?t=7946&highlight=web2book http://www.mobileread.com/forums/showthread.php?t=9754&highlight=web2book