"Eliza" is a bit unusual for Zachtronics as it's not a programming/puzzle game but a visual novel. But it's excellent and I think it's one of their most under-appreciated games. It's well-written, well-acted, and very prescient. Highly recommended!
Maybe it's because (unlike others in the VN space) it totally eschews unusual settings, gimmicks, or flashy set pieces to sell itself... I only bought it because I liked the tidbits of story in Shenzhen and Infinifactory, by the same author. Every part of it is unbelievably strong though.