exclude some forums.. not the normal way though

[Acers]

I want to exclude some forums from new search and daily search. I know the normal method of comma seperated values
eg
do=getnew&exclude=73,74,75
etc
is there any way i can define some variable in global_start hook (or anywhere else) like
$excludedforums=(list of forum ids)
and then do it like
do=getnew&exclude=$excludedforums

the idea being that with multiple skins i need to change at one place to reflect everywhere.