[go-nuts] How to do multipart http get requests using mime/multipart?

I've seen several discussions about using mime/multipart along with
net/http/request to create multipart post requests (for instance, here:
https://groups.google.com/d/msg/golang-nuts/Zjg5l4nKcQ0/wWEw6rJNkJ8J) and
this blog post
(http://matt.aimonetti.net/posts/2013/07/01/golang-multipart-file-upload-example/),
but I haven't found any discussion of using a similar technique to do a
multipart get request for fast concurrent downloading.

I realize the content-length of the data to be downloaded would probably be
needed, but I was hoping to be able to do this in a similar way without
setting up ranged requests. Does anyone know of a way to do this or, if
not, what is an idiomatic way of achieving this in go?