Abstract: In a multi-tenant web services platform, a request is received from a first customer requesting that a second customer be allowed to use a computing resource associated with the first customer. Control of the computing resource is transferred to the second customer based on a constraint selected by the first customer. A first portion of a cost associated with the computing resource is billed to the first customer. The control of the computing resource by the second customer is terminated in accordance with the constraint selected by the first customer.

Abstract: In a computing environment, a request for computing resources is received by an entity. A quantity of resource slots sufficient to fulfill the request is determined and associated with the entity during a portion of a recurring time period. The resource slots can be associated with other entities during other portions of the recurring time period.

Abstract: In a computing environment, a request for computing resources is received by an entity. A quantity of resource slots sufficient to fulfill the request is determined and associated with the entity during a portion of a recurring time period. The resource slots can be associated with other entities during other portions of the recurring time period.

Abstract: A technology to optimize virtualized computing is described. Usage of a plurality of virtualized computing instances is identified in a virtualized computing environment. Purchasing configuration optimization rules are applied to calculate an optimized purchasing configuration for the plurality of virtualized computing instances in a virtualized computing environment. The optimized purchasing configuration is recommended for the plurality of virtualized computing instances.

Abstract: A virtual computing resource provider may implement reconfiguration of reserved compute instance marketplace offerings for requested reserved compute instance configurations. A request for listings of reserved compute instances available for resale according to a specified instance configuration may be received. Reserved compute instances may be identified that are reconfigurable to satisfy the specified configuration (e.g., a particular type, location, or reservation term length). Listing may be provided for reservation by a client that include modified listings that describe a configuration for the reconfigurable reserved compute instances that satisfies the specified configuration. In some embodiments, a reservation request for a modified listing may be received, and in response the reserved compute instance associated with the modified listing may be reconfigured (e.g., modified, upgraded, downgraded, or term adjusted) as described in the modified listing.