I have a MT weblog configured to output the html files to my "public_html" directory. Is there any way I can have MT output an html file in a subdirectory a well?

Example:

create a "trees.html" and output that file to the "public_html/my_gallery/albums/trees" directory. Meanwhile continue to output the index.html to "public_html" directory.

use an absolute path.

you can do strange things like that with archives but if you're wanting to stick index templates in differnt folders I don't know if you can do that.

I would suggest sticking all of your index templates for that blog into a common include directory and then use PHP or SSI or something to include that file from other places on the site. That's what I do for my index templates ...