Thanks Tiompan, Roy and LS for the clarification on the timeline of the pyramids in relation to Silbury. I posted this back in 2007 (doesn't time fly) - don't suppose I would make a similar post today as a certain amount scepticism has set in since then. It seems a bit naive reading it now, nice comment by Wysefool though (RIP).

Here it is!
http://www.themodernantiquarian.com/forum/?thread=44983&offset=25