Twilio - Brings voice and messaging to your web and mobile applications.
TrafficMonitor - TrafficMonitor is a network monitoring suspension window software in Windows.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
NetBalancer - NetBalancer is a Windows application for local network traffic control and monitoring.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
FreeMeter - Monitor network bandwidth (C#.NET 2k/XP+). Desktop and Systray graph.