Realizing elasticity in cloud applications today is often a cumbersome process, requiring applications to integrate with services like elastic load balancers and/or be rewritten to accommodate distributed frameworks like map/reduce or cluster-based operating systems. In this paper, we introduce the concept of ElasticOS, which enables a process (or even a single thread) to stretch its associated resource boundaries across multiple machines automatically, expanding and contracting on demand without requiring the application to be re-designed or configured with a complex combination of additional tools and frameworks. Our initial implementation within Linux 3.2 and a study of a MySQL execution trace provide hope that the ElasticOS vision is achievable.