Set up a shared wish list on Amazon... he'll add what he wants to it, and that will include passive 'meh, maybe one day', all the way through to 'now now now!!!' pressies. Just pick and choose from there.
On mine I have casual comics, chocolates and drill bits, all the way up to bench planers and other power tools.
There may be guys out there that like socks etc (seems to be the go-to), but to me as a guy, they wreak of can't be arsed... the same way picture frames, candles and assorted soaps are used for women. Apologies to those women out there, my mum had a colleague who without fail would cycle these three presents and it's burned into my memory!
If he works away from home, maybe personalised calendars with kids pics?
Or if you're strapped for cash, coupons... including get out of argument free (my favourite one BY FAR), or that thing he constantly bugs you for in the bedroom (trust me, this one will be greatly appreciated)... of course it goes both ways... him getting up to a crying baby at 2am, massage, cleaning... I don't know, whatever takes your fancy.