OctoPerf - OctoPerf is a SaaS load testing solution, based on JMeter.
Loader.io - Loader.io is a simple cloud-based load testing service
StresStimulus - Load testing tool for websites and mobile that works with hard-to-test applications.
Loadium - Performance Testing & Load Testing Tool
SmartMeter.io - Performance Testing with Enterprise-Level Features with a familiar jMeter interface
LoadFocus - Cloud Testing Infrastructure | Cloud Testing Services and Tools for Websites & APIs.