I have been poking trough the MapTools source which of course led to tinkering, and in my tinkering I created a command /settokenproperty (or /stp for people like myself who dislike typing).
So far its pretty boring and can only set static values on selected tokens, e.g.
/stp HP 10
Which is if I am to be honest not that useful at all, so I started trying to figure out how to make it a little more dynamic (and still working on Java 5).
It then occurred to me that I could modify the settokenproperties command to use the dice roller using the familiar [] syntax (read on before calling me crazy

Say you wanted to apply damage to a token or set of tokens,
create a macro with
/stp HP "[HP - Damage]"
Assuming that the token(s) have the HP property (if not why are you trying to set it?) you should be prompted (once each run of the command, no matter how many tokens are selected) for "Damage" and have the HP property = HP - Damage
Using DnD 4e with Temporary Hit Points? no problem, assuming the property is TempHP you could make this macro
/stp TempHP "[TempHP - Damage]"
/stp HP "[HP + min(TempHP, 0)] "
/stp TempHP "[max(TempHP, 0)]"
Using DnD 4e and your mage loves firing fireballs at monsters with fire resistance? Well that can be done too! Assuming Fire resistance value is
in FireRes
/stp TempHP "[TempHP + min(0,FireRes - Damage)]"
/stp HP "[HP + min(TempHP, 0)] "
/stp TempHP "[max(TempHP, 0)]"
(In my defense I said you can do it, I never said it was either elegant or straight forward!)
Since it would use the standard dice roller I guess you could even make a macro to roll the ability scores for adhoc NPCs.
What it wont be able to do is make decisions (i.e if toHit > AC HP = HP - Damage) or refer to any other variables outside of the token being modified.
What I would like to know before I start continue down this path is would people find this useful? Would this be an acceptable short term alternative to scripting? I am also open to other suggestions or additions to the proposal
Craig