I like to think while I am doing certain things, one weird thing that helped me have a very intense thought process was watching multiple entertainment video streams at once, my mind was drawing independent conclusions while being stimulated, ironic considering video entertainment is often used to numb the higher thought process. It was related to the videos and yet related to my innermost thoughts at the same time, it's probably because the mind can't focus on any one stream and therefore plays around with itself. The choice of video is obviously important too, it should definitely not be porn! :D
Thinking in silence does work though, it's just lonely here.