Magazine subs a good idea, and one use each year, changing titles if not quite right...
However, answering the question...
All depends how old he is...
younger than say 50 and a music magazine might be an idea (R2 good for roots / folk / blues / etc) and reasonably priced. Q is dearer andnot as good as used to be.
Car mags usually popular - plenty of specialist titles out there if he has a particular favourite marque.
Also, many mags catering for older mechanical items, and not just cars, but also tractors, lorries, canal boats.
Gardening mags abound, along with specialist titles if he's into keeping chickens etc!
Plenty of camera titles too if he's into photography, some even specialise in a particular make.
Of course Nuts, FHM etc may be popular, but maybe not around the Christmas tree?
Maybe best pop down to the nearest Borders or mega-supermarket and spend some time browsing?