Moving beyond the big players - Google, Yahoo, Bing, Ask, DDG (who all obey "nofollow"s), are there any search engines out there which deliberately disobey
rel='nofollow' links and
Disallow rules in
robots.txt files - either by default or as an option?
(Note: A very similar-sounding question has been asked before (Do all search engines obey nofollow rel attribute on hyperlinks), but it was clearly interpreted by all the answers as "do all major search engines obey rel='nofollow'", to which the answer is basically "yes". This is not my question.)