pdfsizeopt
I came across a tool today that allows for optimizing the size of pdf files. pdfsizeopt is a command line tool that will reduce the filesize of pdf files. Something like this immediately caught my attention because of my interest in document generation and automation and saving some filesize can be a big win if it can be done automatically.
Looking at the code I noticed there hadn't been any updates in a while and python support is 2.x only. Were it not for the extreme lack of time I have this would be the sort of project I'd consider creating a Python 3 compatible fork of. I'd probably need to be paid some money to be able justifying making something like that though.