Team-building exercises. I worked for a software company that was obsessed with them, usually in inconvenient locations and built around tasks that were 'fun' (if you think mildly embarrassing yourself in front of people you don't really know and don't wish to know is 'fun'). Hated all of them, except the one that proved our gnarly little corner of corporate communications was the most united team in the organisation (albeit, largely united against the organisation).
I've never been prouder of a 'team' when our translation and localization crew was invited to a voluntary activity that would involve going to a local park to devise, script and shoot a short film. This was to take place on a working day, and it just so happened that it was raining heavily when the big day dawned. With no communication between us, 12 different people independently looked out of their homes, saw the weather, guessed what kind of mud bowl the park would be, and concluded that they could log on to work from home (entirely permissible, just mail your line manager) or go to the office rather than the park on the grounds that it would be dry and there would be coffee. After all, the whole thing was voluntary and we could hardly be disciplined for turning up to work.
It got better. Most people went to the team building, so we didn't have a long task list that day. So we could tidy up a few loose ends and be done by lunchtime, while a bunch of corporate 'true believers' spent a miserable wet day shooting crappy videos of each other in a landscape resembling Ypres in 1917.
And, best of all, three days later we got snotty emails from the team-building coordinator to say how disappointed she was that nobody from our team thought it was important to attend the event and, as a result, we wouldn't be invited to the follow-up meeting (sorry, 'premiere screening') where everyone would watch these films and provide positive feedback. I suspect one person in the entire organisation thought this would be a punishment rather than a perk.