1. A computing system comprising: a memory storing an interactive request manager component in the form of computer executable instructions, wherein the interactive request manager is configured to manage requests for computing resources by users of a program execution service (PES), and wherein the PES provides a plurality of computing nodes that are each configurable to execute one or more programs of multiple users of the PES, the program services comprising (1) to allow a user to customize distribution of a workload across multiple computing nodes of the plurality of computing nodes and (2) a load scaler configured to scale computing resources in response to variations in workload; and a processing unit coupled to the memory, the processing unit programmed by the interactive request manager component to at least: receive a request from a first user to share, with users of the PES, a first virtualization environment generated for the first user, the first virtualization environment including an operating system, at least one user program for execution on a subset of the plurality of computing nodes, the load balancer, and the load scaler; update a list of virtualization environments available for selection by users of the PES to provide an updated list of virtualization environments that includes information related to the first virtualization environment; provide the updated list of virtualization environments to users of the PES; receive a selection of the first virtualization environment that is included in the updated list from a second user of the PES; and generate a second virtualization environment for the second user, the second virtualization environment based at least in part on the first virtualization environment.