I work in a stockroom at a warehouse. We supply and maintain uniforms for all kinds of companies.
There are small portions of the day when I actually use my brain or do an activity simple enough I can listen to a podcast or music on headphones. Sometimes there's a project that lasts all day. Lately it's been weeks where in an 8 hour day I spend at least 3 hours looking for something to do/standing around. It just has to do with when the incoming/outgoing trucks come. 
We've cleaned and organized to the point where there's nothing left to do. Today I almost fell asleep. I bring a book but if upper management caught me reading I don't think they'd love it.
Edit: I think I poorly worded the question or something. Yes I understand that to continue paying my bills I have to work. I just desperately want to be less bored out of my mind. Thanks to any past or future commenters