The cost of the terminal is about USD$4, 600.
Airtime pricing is quite complex and varies by provider. The bigger reseller companies tend to have better rates. A one year contract is usually neccessary.
Phone calls are charged by the minute and data by the Mbyte. For the standard data rate of 32kbps a monthly fee of about $600 includes 300 minutes of phone calls at $0.89 per minute and 25 Mbytes of data at $14 per Mbyte.
Of course you have to pay for any additional minutes or megabytes if you exceed your allocated bundle. One has to be very careful not to run up huge bills while surfing the web, or while your laptop decides to download Windows SP3.
The lowest price option for 9.6 kbps includes no minutes or Mbytes and is only about $44 per month but you pay as much $1.50 per minute for calls and $22 per megabyte for data.
For the big spenders, $1300 per month will buy you 150 Mbytes and 300 minutes of phone traffic and if you want to bump that up from 32 kbps to 128 kbps you would pay an additional $350 surcharge.
Here is a pricing table example from ocens.com. Apparently one can get substantial discounts on airtime from the larger providers.
When you get to the high end bundles, one should really start considering a VSAT service with a fixed monthly price for unlimited data, although the $600/month bundle (25Mb/300m) at 32kbps might be the perfect solution for vessels that just need email and the odd weather report.
Iridium OpenPort Specifications
Height: 9.06 in (230 mm)
Diameter: 22. 44 in (570 mm)
Weight: 24.25 lb (11 kg)
3 independent RJ11 ports for simultaneous use
IP-based, 9.6-128 kbps (configurable) with per-MB pricing for airtime
Height: 7.78 in (200 mm)
Width: 9.84 in (250 mm)
Depth: 2.17 in (55 mm)
Weight: 2.98 lb (1.35 kg)
LEDs and configuration through Web browser interface