I have looked but I can't find it. There is a bicycle security item that uses a key in the headset.
You turn the key to one position and the handlebars lock in place at a 90° angle to the front wheel, (for riding).
You turn the key to another position and the the bars move freely, (so nobody can ride off with your bike).
And the last position locks the bars down parallel to the front wheel, (for storage or shipping).

I'm pretty sure I saw it here on BF about a year and a half ago, but I can't, for the life of me, remember what it was called.
I think it was either made in the UK or Holland, (or at least marketed there).