What Eats Up Your Time?

I have found lately that I spend the majority of my time waiting. I wait for video to encode, I wait for Windows to load, I wait for a phone call to be returned, I wait for an email response... I wait. I'm not sure as to what portion this would occupy on a pie chart, but I am sure it is a large slice. I would like to be able to minimize this time as it is wasted time. Here in lies the problem. I struggle with moving from one task to another while the first one is unfinished. I stay up sometimes till 3am or longer to complete a project I started at 6pm just because I have to finish it or else I will not get any sleep at all. I would just lay in bed thinking about what I could be doing and what would come next on the NLE timeline. After speaking to my father, I realized that he too must finish something before moving on. After speaking to several men, they too have this same desire/motivation to complete something before moving on to something else. Another example: If I am working on a PC and need a tool that I don't have readily available, I will go and get it and leave the closet door open, the toolbox laying out and grab the tool I need to continue the work. Once I am done with that part, I do not go and replace the tool, put the toolbox back and shut the door, I continue working on the PC until it is fixed, then I clean up my tracks.
So, even during waiting, I am still focused on completing the one task at hand. It would be hard for me to start something else and then pick back up where I left off on the other project not because I can't multitask, but because I prefer to finish the job I started. Anyone else find this difficult? I think this is the root cause of my wasted time spent waiting.

Some questions:
-Do you deal with something like this effectively?
-What do you spend the majority of your time doing?