Iridium is quite a handy alternative for cruisers.
This system works on a network of many low earth orbit satellites rotating around the Earth, just a few hundred miles up, as opposed to 22,300 miles for fixed satellites. The closeness of the satellites allows for small, low power handheld terminals.
The satellites are moving all the time, rising and setting and zipping across the sky, and you can usually 'see' more than one at a time.
During a conversation, you may be handed off from one setting satellite to another, as they rise and set. In the early days, your call would sometimes be dropped during the hand off, but it was still a worthwhile service if you could tolerate a few dropped calls. I have not had recent experience, but hope that this has been improved.
The handheld terminal costs about $1300 and then you pay about $1/minute for voice calls. You normally have to buy $500 worth of minutes up front which, I believe, expire after 1 year.
You can also hook a laptop to the phone and do slow speed data (8Kbps) and email, but it is certainly not suitable for browsing the web.
One advantage of the portable Iridium phone is that you can take it with you when you go ashore and you could even take it with you in a life raft if needed.
It is really handy when you enter a new country and your old GSM prepaid SIM card does not provide coverage.Howard [ Just Imagine ] 01-Aug-2008