Places to Stick Signs

I can see it might be a bit of a problem for the Highways authorities. They need to stick a sign up, but haven't got room to put it. Can't put it on the road, it would inconvenience the motorists. Can't block the pavement - there'd be complaints. Ah! But there's always the cycle lane. No-one uses that do they? Especially the contra-flow ones that bypass busy roads in the City. The only people who will compain are cyclists, and everyone hates them anyway.