Well, my sleeping schedule has been messed up pretty badly lately. Many reasons like pulling an all nighter and crashing afterwards, partying, not having time or a good enough place for a nap during my day etc. But I'm not giving up. I believe getting a wake-up routine established will help a lot. Working on it.
I also started recording my sleeping times to evaluate how I'm doing and if it's really working, i.e. if I get more time out of my days. I'm using an app called 'Timesheet' which has a csv export. I'll post the results here as soon as I finished the first month of recording. Right now it looks like I spent an average of 7.5 hrs sleeping each 24hr period. Not impressive.
There are many references about historic persons trying polyphasic sleeping. Most notably probably Buckminster Fuller who invented what he called the Dymaxion sleep cycle in the 1950s. This interview explains the word Dymaxion and talks a bit about his life. His idea was to sleep 30 minutes every 6 hrs and he supposedly did it for quite a long time until his wife got fed up or he adjusted to his business partners' schedules. Whichever version of the story you tend to believe more.
Before that many people are believed to have been sleeping polyphasically like Leonardo da Vinci and Thomas Edison. But those reports usually do not withstand biographical scrutiny.
More interestingly are the recent polyphasic sleeping endeavours, which are mostly for military use. In extreme stress situations such sleeping patterns keep your total sleeping time down which can save your life, but the general alertness and performance is worse than with a full nights rest. It's a great thing when you're sailing around the world single-handed and want to make sure not to crash into another boat, but probably not a good idea if you want to work creatively all day long.