My beloved took me out this weekend and bought me a marine aquarium (thankyou!).
I subsequently spent the rest of the time worrying about the specific gravity of my water and arranging live rock on a bed of coral sand. Still, it should keep me occupied - and distracted given that it will sit in the corner of the study. It is only 58 litres so it might take a bit of setting up, but hopefully it will be a successful first foray into the colourful world of marine fishes.