Actually there are several things that ought to take my time (a bit like photography really) but as I've spent the last 20 years spending my Monday - Friday living in hotels in different parts of the UK, and even for a while in Paris, I have a ready-made excuse for not doing stuff - "I just don't have the time!" Obviously we'll not investigate that claim too closely
There are a couple of pastimes that are on my list of things to do:
a) Play guitar again. Difficult to believe that 40 years ago I was semi-pro and earned more at the weekend than I did during the week doing my real job. Have barely touched a guitar in the last 30+ years
b) Do something with my collection of Meloday Maker (a UK weekly music paper). I have from Aug 68 - Apr 77 so I'm sure there's something useful I could do with them.
One day ...