Just post the modification on that particular site's own mod database or mod site. It doesn't make sense for competitors to come to vB.org for modifications.
I don't want to register will multiple sites, figure out their coding standards, jump through the hoops to release a modification, fix the mod several times due to forum changes and definately don't want to do any sort of support anywhere else.
I don't own PHP/IPB and don't want to even pirate it to learn the system, I do however want to extend the usage of my mods.
If I changed my [ code ] tags to [ quote ] and changed the attachment to a link on my site, would that be allowed?