MiFi is the latest product to leverage the rapidly expanding 3g, 3.5g and 4g wireless data networks to provide internet access for computers. The basic idea of MiFi is that it connects to the data network, and provides a local cloud of coverage to laptops within a short range, sort of like a WiFi connection. The advantages are that the MiFi devices are portable, and can be used anywhere. It means that you can have a small network cluster almost anywhere you want.