What are some alternatives?
When comparing NServiceBus and Beanstalkd, you can also consider the following products
IBM App Connect - IBM App Connect is the all-in-one integration tool for connecting apps, integrating data, building APIs and acting on events
RabbitMQ - RabbitMQ is an open source message broker software.
Apache Camel - Apache Camel is a versatile open-source integration framework based on known enterprise integration patterns.
Amazon SQS - Amazon Simple Queue Service is a fully managed message queuing service.
Software AG webMethods - Software AG’s webMethods enables you to quickly integrate systems, partners, data, devices and SaaS applications
CloudAMQP - CloudAMQP automates every part of setup, running and scaling of RabbitMQ clusters. Available on all major cloud and application platforms.