He did say he was interested in returning to Celtic in a coaching role a few months ago. He's managing a team called Landskrona BoIS and it looks like they're a pretty average second division side (they finished 8th last season in a league of 16). He hasn't managed any competitive games yet, but his first game in charge is at 4pm on Saturday, might be worth looking out for the result if he's potentially a future Celtic manager. He only signed a 1 year contract with the current side.