i've received some from answers.com, ask.com, altavista.com and a few others. i think some of them use the g/yahoo/msn search engines though but i'm not sure. i don't remember seeing any hits coming from lycos either. nonetheless, the traffic i get outside of the big three is not very appreciable.
these other search engines could be a great place to employ some search engine marketing though, and you might want to look into that.