GENS
GENS is a calculus (an abstract VM) of explicit lexical environments by Mario Blazevic; on top of GENS, you can implement the lambda calculus, your favorite object-oriented languages, etc.- In proceedings of Multiparadigm Programming with Object-Oriented Languages (MPOOL 2001) International Workshop:
Mario Blazevic and Zoran Budimac, An Environment-based Multiparadigm Language, p. 97.