If you have an iPhone 3G or 3GS you can use your handset as modem for your laptop by a process known as 'tethering'. (You need to upgrade to iPhone OS 3.0 to use this feature).

This enables your computer to access the internet via your iPhone's 3G cellular data connection.

First contact your mobile phone operator to activate tethering. In the UK O2 charges £10 per month for a tethering 'bolt-on' that allows you to download 3GB of data per month.

Remember this is just for the use of the iPhone as a modem - the normal unlimited data plan still applies for data downloaded in the phone mode

Once your operator has enabled tethering:

• Click on Settings
• Click on General
• Click on Network
• Now click on Internet Tethering and switch it on

You can now connect your laptop to the iPhone via USB or wirelessly via Bluetooth.

The iPhone connection will be listed as an ethernet adapter (En4) connection.

The network setting should be set to Configure: Using DCHP

Don't forget to switch tethering off when you have finished.