I sugguest the only tokens available be:
%T - the actual post title
%D - the gmt date the post was created
%N - the node_id

It would be user setting, blank by default (in which case it's just the node_title in the title). It would be have a 12 character limit (<INPUT TYPE="text"..., and anything other than %T %D and %N would be represented litelarlly, so that
perlmonks (%N) %T
for this post would translate into
perlmonks (128020)(crazyinsomniac) Re^2: http://perlmonks.org: Title, or Trash?

That'd be pretty easy to implement, some potential code (which should work if some pmdev-er wants to submit the patches), on user settings (with appropriate html around)

[{textfield:customnodetitledefinition,12}]
# or, in case that don't work (i don't recall, i'll have to check)
[{setvar:customnodetitledefinition,12}]
[download]

my $V=getVars $USER;

my $pt = (exists $$V{customnodetitledefinition} and
          defined $$V{customnodetitledefinition} )?
         $$V{customnodetitledefinition} : undef;

return qq{<TITLE>$$NODE{title}</TITLE>} unless $pt;

$pt =~ s/\%T/$$NODE{title}/;
$pt =~ s/\%N/$$NODE{node_id}/;
$pt =~ s/\%D/$$NODE{createtime}/;

return qq{<TITLE>$pt</TITLE>};
[download]

 
___crazyinsomniac_______________________________________
Disclaimer: Don't blame. It came from inside the void
perl -e "$q=$_;map({chr unpack qq;H*;,$_}split(q;;,q*H*));print;$q/$q;"

Regards...	Stefan
you begin bashing the string with a +42 regexp of confusion