While surfing through google images last night I came across an interesting web site. I haven't looked at it very closely but on the home page it talks about chakra meditations. That was what I referred to some 20 pages back when I mentioned the finger action I incorporate into my meditation.

Here is a link if you are interested. I see on the menu mention of the sangha too.

http://www.purplebuddha.co.uk/meditation.html