Maybe a list of topics, than we can choose the one for the week, mine would be;

"burial chambers were almost always built simply where suitable stones were to be found in the landscape."

whether cromlechs are sited in a territorial position, for example delineating the land of a clan or tribe, or whether they are sited next to a convenient quarry, stone/stones, - a capstone. As always we are given various sides of the argument, thinking Brian Johns here on Neolithic Quarries and their 'sacredness' which of course he takes with a pinch of salt....

http://brian-mountainman.blogspot.co.uk/2012/08/the-neolithic-quarry-obsession.html