Shameless plug: I built a small library to provide more Expect-like features in Ruby, since I didn't care for the interfaces exposed, for application development. Presently works on Linux and OS X for 1.9.3, and Linux for 2.0.0 (OS X untested, but assumed good)

https://github.com/cwuest/expectr

As does Perl.

I used expect back in the day for a number of purposes.