Stumbled across an old church that I found impressive. Subsequently, I've found out that it is a controversial place - and that the signpost warning you to dress respectfully is not a mere suggestion. St Nicolas du Chardonnet is a bastion of a "traditionalist' right wing movement that occupied this church building in the 70s.
That said, the church is an impressive work of love and art and a clearly still very much in-use within a society that has always been sceptical of religion and clings jealously to the separation of church and state, and France's self-realisation as a secular state.
Here are some images that I took from my mobile phone (one can sense it that this is not a very welcoming place for such 'unholy' activity as picture taking):