OK, so I thought I was being original - doh! I'm like; so 2005...
I just added a search component to my blog and found
Rachel's blog http://doublingchallenge.blogspot.com/
where everyone is doing it,
Also, they generally appear to be targeting 1 million, which is also quite different. I was thinking that if I or anyone else could get to my £4096 target then why would you stop there? but for now I want to take one month/step at a time and see if this is possible; if so, I guess it could be extended, I'll think about it more next year...