Yup, the Delta32 version of CCR5 is pretty nice. Its more of a "strongly resistant" than an "immune" though, and may mean being more susceptible to West Nile Virus. In the modern world thats a pretty good deal, but was probably less so when humans were doing most of their evolving.

See wikipedia: http://en.wikipedia.org/wiki/CCR5_delta_32#CCR5-.CE.9432

There's another gene with a variant that confers similar resistance to noroviruses, also called stomach flu.