ElasticWindow disappeared when his publisher decided to give up. That is when members of the forum asked for a replacement that I issued RubberViews.
Technically, it is not exactly the same, since RubberViews is a class that can be dragged over windows and container controls. But I created RubberWindow and RubberContainerControl which replace Elastic Window and Elastic Container Control. They can be used as a drop in replacement.
In terms of performances, I believe RubberViews is a bit more advanced than Elastic Window, and needs less tweaking.
You can download an evaluation project at https://RubberViews.com.