First, the Wi-Fi.
I have had an annual subscription to Broadband Xpress, a marina Wi-Fi service for two years. You can check their website for a list of marinas and the various subscription or day rates available. (http://bbxpress.net/) They are in a lot of places.
We bought the EZ Connect Modem, for the added range over the built in computer Wi-Fi or a USB plug in. The price is steep, but they have very good tech support at BBX if you have their equipment. You must have a medium or long range antenna of some sort. It's not like a hotel where you can park yourself and your PC in the lobby and hook up.
The second reason to buy the EZ connect, or similar, is that you can put it up on your flybridge and get a vastly superior connection. I then plugged our Apple Airport into the EZ Connect and had wireless Wi-Fi all over the boat. Both are powered by a small 100W 2 plug inverter plugged into a 12V socket.
Second, the Skype.
Skype (Skype.com) is a free download that allows you to "call" other Skype users who are logged into their computers for free. You can pre pay for service to any telephone in 10 Euro (about $13) packets. International calls to/from Canada or the US cost pennies per minute, compared to a dollar or more depending on your cell phone calling plan.
When you have a strong Wi-Fi signal without a bandwidth hog downloading the latest season of Hell's Kitchen on the next boat, you will have a very good connection that you can use for endless calls back to your family. If your son/daughter downloads Skype, you can talk, or, even picture phone, for free. Skype, itself, uses very little bandwidth.
My experience is that with a good connection in a marina, I have not had a problem with bandwidth. I frequently have problems in hotels with free internet as they do not have enough bandwidth, or controlling software, for many users at once. BBX does a good job on this.
Two added thoughts.
There are several marinas with good Wi-Fi and poor/no cell service at the slips. Examples are Fisherman's Bay and Silva Bay. You can phone home without the phone.
There is a Skype application for the iPhone. Once my antenna is set up and the boat Wi-Fi is running, I can log into Wi-Fi with the iPhone, one button, and start making Skype calls using the telephone. If you are going to use Skype with your lap top, you should by a cheap headset. Your calls will be much clearer.
I am not the same "Kevin" as the guy who runs BBX. He has two promos on the website about Skype as this is being written. I have no connection with BBX.