Ask HN: Anyone blacklist employers they wont work for?

Yep. There's a well known firm here in Leeds, UK whose practices lead a lot of folks to say 'ugh, no thanks', me included. There's another firm that makes bogus cellphone towers for spying on protestors who I'd not work for.

Apart from that, the usual - credit firms, gambling companies.

Yes. Several companies have so an bad reputation that i would never work for them.