The recent discussion of parts of speech has inspired this idea for a very
weird one.

A mapword is a word whose entire purpose is to define the grammatical
structure of a sentence. It is a polysynthetic compound of particles, each
morpheme corresponding to the function, role and gramatical relations of
the words following it. Each sentence begins with such a monstrosity, the
rest of the sentence consisting of isolating semantic words which are its
arguments. Here's an example (in English gloss).

n-pat.adj-attrib-pat-sup.vb-pt.adj-attrib-agt-comp.n-agt dog big buy small boy

The smaller boy bought the biggest dog.

Word order is simply mapword : everything else.

Of course, when you start using subclauses things can get seriously

Any thoughts?