I use pidgin as my main messenger, also have skype but don't use it much... The yahoo support for it is decent, not really sure about voice though edit: Try gy

I use pidgin as my main messenger, also have skype but don't use it much... The yahoo support for it is decent, not really sure about voice though edit: Try gyachi for better yahoo chat support. Haven't used it myself, but it seems to be pretty popular on the forum.