almost everywhere: HAProxy. I like the syntax, ACLs, map files, stick-tables... there's too much to say in a single post, but I use it since 2012 and it never failed me, whatever the need, both at home and at work.
kubernetes: ingress-nginx. Mostly because it's the first one I tried back in the days and it just works :). Although I should try one of the haproxy based ingresses, or Traefik, which seems interesting too.