After considering the many views expressed in this thread, I don't think the ethical aspect is really the issue. If it were then hardware modifications changing the original intent of the designer (which most here seem to acquiesce to) would fall into this category also. When it comes to someones "baby" then the division into hardware and programs is not relevant.

The issue is really about what commercial harm is caused to the OEM by modifications to any part of the system. I would contend that no harm (apart from, maybe, bruised egos) is caused to the equipment maker. If a modification were sold commercially such that the OEM were financially disadvantaged then they might have some reason to sue for damages but as modifications inevitably mean that you must have the equipment in the first place then I can't see how this might occur.

Malcolm