Virgin Mobile, owned by Richard Branson, is a wireless carrier with service in Australia, Canada, Chile, Colombia, France, India, Saudi Arabia, Poland, South Africa, México, the United Kingdom, and the United States. Each Virgin Mobile brand works independently from one another, therefore services and devices vary between all locations (not all the same phones and services are available in all service locations). Virgin Mobile works on top of an existing mobile network operator or mobile virtual network operator (MVNO) — for example, Sprint in the United States.
Virgin Mobile offers a large variety of prepaid devices and services including voice, messaging and data. They offer current top devices like the Samsung Galaxy S5 and iPhone 5s. Devices and "top-up" cards are available at thousands of partner locations and independent retail stores.
Virgin offers unlimited plans starting at around $20 per month, Broadband2Go services for mobile 3G and LTE data, and Virgin Mobile custom, which lets you build a plan customized to your mobile needs.
More info can be found at Virgin Mobile.