One of the most "enabling" of the recent computer services to reach the mainstream is VOIP (voice over IP). In a nutshell this means making & receiving phone calls using the internet rather than via conventional phone lines. Why do this? Cost savings basically. If you have teenage daughters, friends overseas or are just a phone-a-holic then some kind of voip service will help make a dent in your massive phone bill.
Me, I've done away with our BT phone line altogether (so no line rental) but still use my existing cordless dect phone AND have an authentic local telephone number that my friends or colleauges using conventional phones can call. I have put my family on similar voip systems so calls between us are free (in as much as we don't pay any more othe that what we pay for our broadband internet).
There are a few options to choose from. I'll start with probably the most known & that's Skype.
it's a free program download for your PC or Mac (A windows mobile version for your PDA phone is also available) which will allow you to speak to other skype users. ideally you'll need a headset with microphone or something like a USB phone that plugs into your compy in order to make calls. it's not impossible to use vai your laptop if it has an inbuilt mic & speakers (though the caller will here their own voice coming back to them which can be offputting so I'd recommend headphones at least).

Optional ingredients are:
Skype
(lots of people use this one, available for PC & Mac)

Gizmo (which I can recommend- can be made to use your existing phone & does not necessarily need your computer on all the timne in order to receive calls, though purchase of an adapter is necessary) - PC & mac again.


Both of these allow free calls to other computer uses using the same software & very cheap calls to regular phones around the world.