Caustic has a vocoder thing as well. Free demo on android, IIRC there's a totally free full version on PC and it costs money on android (dunno why)
So if you can't afford FL Studio (It's like $100 but I needed a DAW and hadn't heard of Caustic at the time) you can check that out
EDIT: Oh, Vocodex isn't part of the main FL Studio thing. It's like Toxic Biohazard or almost all the other fun synthesizers, it's a separate purchase. Fruity Vocoder does exist, however, and is included in the main purchase.