For those of you using Domain Access, you'll recognize the problem: You need domain-specific settings.
Sure we have Domain Configuration module to expose certain settings through a single UI, but what about all kinds of other settings, especially from contributed modules? Adding exceptions in hook_domainconf() or hook_domainbatch() is cumbersome to the site maintainer, and out of scope for the Domain Access project.
What to do?
Well, you can test the Domain Settings module, which steal a few tricks from Deploy and makes it so that any form that uses system_settings_form() can be told to submit changes to a specific domain.

If anyone's really interested in the module, I may make a release. Anyone who wants to maintain it should leave a comment in the issue. UPDATE: I am also considering rolling this into the Domain Configuration module.
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