Download: MicroSIP

Although Skype is normally the first service for making telephone calls over the internet, there are many more apps that use a standard called SIP. MicroSIP is a small program for making SIP calls that can be installed on a USB memory key so you always have it close to hand.

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Installation is simple. MicroSIP can either be installed on its own to a folder of your choosing, or integrated into the Portable Apps launcher. If you don't install into the Portable Apps Launcher you will need to create your own shortcuts, or just remember what folder it is in.

Starting MicroSIP displays the dialler keypad. A slight disappointment is that there is no way to access the Settings or Account information through the dialler. Instead you have to right-click on the MicroSIP icon in the Notification Area to find these settings.

The dialler is very easy to use, either click on numbers or type them to enter. There is a basic Contacts list as well, just name and number. Without search it might get hard to navigate for long contact lists but it's fine for a short list of important contacts.

There are many different SIP providers and many offer free accounts, such as Freespeech, some even come with local dialling codes. Calls between SIP accounts are normally free but there are usually charges for calls to landlines or mobiles.

It can even use a webcam, which was more than we were expecting. It needs to be enabled in the settings menu but there wasn't anything beyond that and it started working with our Microsoft Lifecam Studio.

The Account window is also very functionable but this does at least make it very clear what information is required. There is some help on the MicroSIP website although all of the required information should be provided by your SIP service.