Sleeping while singlehanding
I believe that Robert Manry who crossed the Atlantic in his 13 foot sloop "Tinkerbelle" used a bucket on a line that he tossed off the bow of his boat each night to act as a sea anchor. The sea anchor would cause his boat to basically stop in the water, and this would enable him to catch some sleep each night, though I'm not certain how much. It should also be possible to heave to for some sleep time, particularly if one used a sea anchor in conjunction with heaving to to prevent the boat from drifting backwards.
In today's world, with the greater volume of sea traffic that exists, some sort of alarm system, perhaps like the CARD system which sets off an alarm whenever it picks up a radar signal, could be used to avoid being run over in the middle of the night by some giant.
This system obviously would not work if racing offshore, but for one who is in no big hurry it might solve the sleep problem a bit better than catching catnaps for weeks on end.