Shareable/reusable scripts

I have multiple build projects for over a dozen different components. As Bamboo On Demand doesn't support user installable plugins, I have to rely on the use of custom scripts. Now I find myself copy-pasting scripts from one build project to another over and over again. Every time I have to make a chance, all copies have to be updated.

It would be a very easy and powerful way to extend Bamboo without having to write plugins, if the admin could write simple shell scripts and make those reusable in build and deployment tasks. I want my scripts to show up in the admin section as "Shared scripts" next to "Shared credentials". When creating a new task I want to simply select one of those shared scripts and provide additional command line parameters if necessary. That's it. No editing or fiddling with the code, no copy-paste errors, no more updating scripts across all projects. Scripts could even be shared in the community.