I think we need to get some terminology worked out here. The naysayers in this thread are lumping rom hacks and homebrew into one word. Homebrew is unauthorized software written from scratch (or from another brewer's work) to run on a device. You can argue that they should get a licence for that, but the company honestly wouldn't care unless it's on a modern device, used for piracy (emulators, dumping games), or it imitates one of their products (but if you're going to do that you might as well just make a rom hack.) Rom hacks are a sub-type of homebrew where people edit roms and violate copyright laws. Most of the time the new code is uploaded as patch files, and to my knowledge are legal until they are applied onto a rom, but different communities have different rules and Arseen makes it clear what this place thinks about it.
I probably just stated the obvious, but maybe it will help clarify what I think DC99 wanted to get out of this thread.

I think homebrew is really interesting, so I hope by morning people are talking about neat homebrew instead of worrying about links and rom hacks.