I have two blogs and I'd like to allow each to archive sequentially in their own respective directories. The default setup creates globally sequential filenames, meaning one category could have 1, 5, 6, 9, 10 depending on post order.

My goal is to allow each to archive sequentially (1, 2, 3..) in their respective archive directories.

On the surface it seems possible since the blog menu pages show the number of entries, N. The next entry should be N+1.

I don't see how this would be possible, given that MT assigns the entry ID sequentially across all blogs. The number you see displayed for total number of entries is not retained in a field anywhere, it is counted each time MT needs to display the total (probably with the same routine it uses to calculate the value of <MTBlogEntryCount>).

So you'd have to figure out to do incremental calculation in an Archive File Template in order to name the files that way - and <MTBlogEntryCount> isn't an acceptable tag for usage in an Archive File Template.

There is the EntryNumber plugin, which numbers entries in chronological order and can be used in an archive file template. Maybe it would help you out? ^_^

Now that looks like a sweet idea!

I'm also wondering how this is done on some of the bigger blogs like Gawker or Engadget do it.

http://www.engadget.com/page/2/

http://www.gawker.com/index.php?page=2

They sequentially order their archive pages. It isn't necessarily the week of the year, and or day of the year. Do they have their own custom plug ins too?