What would happen if you accessed your blog one day and all of the posts were going? Or the blog itself was gone?!
I don't know how likely this is, but I decided to make a back-up just in case.
I did this in two ways:
1) I exported the blog (using Settings, Other, Export Blog)
2) I used Wget to capture a copy of the blog
The command I used for this was as follows:
wget -rH -Dpetermccullagh.blogspot.ie,bp.blogspot.com -k -l 0 http://petermccullagh.blogspot.ie
The parameters are as follows:
-r tells Wget to work "recursively", i.e. to get the pages and files that are references in pages which it is processing
-H means that it is not limited to the same host. This was needed because my images (which I wanted to fetch) are on a different host
-D told Wget which hosts I wanted it to include. The second one is for the images
-k converts the links to refer to local (relative) addresses after the download
-l 0 turns on "infinite recursion", so Wget will fetch pages, which fetch pages, which fetch pages etc.
So now I have a local copy of my blog with relative links to other pages and images from the blog.