Assign node automatically based on title keywords

I have searched and can't find anything on this, but wondered if there is a module, snippet etc to automatically assign a node via keywords in the title. Assuming there might be more than one keyword corresponding to different terms, the node could have multiple parents, possibly distant parents (I know there is a module for that).

This would be very useful on sites with large, complex taxonomic trees, as it is quite a job to trawl through the taxonomic structure when writing a node looking for the right category/ies into which to put your post (with levels depicted as -, and --, and --- etc). I assume that this kind of hack would give a list of possible terms to use as parents as part of the preview, and you can click those you would like to accept.

thanks in advance

Mark