If you have a Windows Mobile or Symbian s60 smartphone and a flat rate mobile broadband subscription e.g. via MTN 3.5G or GloMobile 3.5G, you can setup your device to serve as a WiFi hotspot. As such, you and others can use your laptops and any other devices with wifi to get online and surf, email, instant message, et al.
For Windows Mobile smartphones, download and install WMWifiRouter.
For s60 smartphones, download and install JoikuSpot.
Using WMWifiRouter, my Samsung i900 Omnia (which runs on a Glo 3.5G connection) currently serves as a hotspot at home, allowing me to connect a range of devices to the internet wirelessly. Setup took a few minutes and was fairly straightforward.
Once again, the beauty of convergence in mobile technology.