CELLPHONES - Saudi Arabia and around

Short Story:

If you have an unlocked, quad-band GSM phone you can use it anywhere in the world, and get a low-cost SIM card here in Saudi Arabia.

More Detail:

Cell Phones can work on different frequency bands:
GSM 850 / 1900 For use in North America only
GSM 900 / 1800 For use in Europe, Africa, Asia Pacific (excluding Japan & South Korea), Australia, New Zealand, Brazil, Caribbean (excluding Bahamas & Bermuda) and the Middle East.
WorldWide GSM Coverage map(s) are HERE from the GSM Association.

Many phones are "Quad-Band" and work everywhere. Most are "Unlocked" except from some subsidized 'deals' in the USA where they are locked to one company (many times you can get these phones unlocked if you've had the service for awhile...try calling your service provider and be persistent).
If you have an unlocked, quad-band GSM phone you can use it anywhere in the world. There are International SIM cards available that work anywhere, at a higher rate. Inside Saudi you will want a low-cost local supplier.

If you need a cheap cell phone after you arrive, you can easily get one here at the malls in Jeddah or with a quick trip to Thuwal, the town just outside of KAUST. Nokia phones are anywhere from 100-500 sar depending on features. ($25-125 US Dollars)

[Update Feb 2012]
For KAUST employees, students and family members of those people, KAUST IT Now offers personal cell phone plans through it's Enterprise account with Mobily. It's by far the best deal on mobile service you can get. No monthy fees, no signup costs, better rates, half-price calls to other people with the KAUST IT Plan (like all your family members who also get at SIM card through KAUST) and cheaper mobile data rates. Contact Kaust IT for signup information.

Inside Saudi, the cheapest seems to be Mobily : http://www.mobily.com.sa/wps/portal and you can get recharge cards at the KAUST supermarket.. You can get a SIM card at the airport (Sometimes..??) and many other mobily on-the-street stores. No hurry if your International SIM works..

There are good international SIM card deals, example: https://www.telestial.com Also: http://www.telestial.com/view_product.php?ID=MSIM-PP02
It's really nice having the phone work anywhere in the world when traveling...

These guys: http://phonecard.bootsnall.com/saudiarabia_sim.htm apparently will send you a Mobily Saudi SIM card before you get to Saudi.
And they also have the International SIM options: http://phonecard.bootsnall.com/sim_cards.htm and deals on Phones.
BUT: Shipping from USA TO Saudi Arabia is expensive foe these SIM cards ($49).. so best get in USA.

What's a SIM Card??

sim-card-100.jpgA SIM card is a small chip (See photo) about 2 cm long, that contains information about your phone service, such as your phone number, user ID, billing information and rate plan, and authorizes you to make calls on a network. All GSM (Global System for Mobile Communications) handsets require a SIM card - your handset’s interchangeable memory. This means you can make and receive calls on any unlocked handset to your SIM card’s telephone number. Changing to another phone company is as easy as inserting a different SIM card into your phone. More?? See: http://en.wikipedia.org/wiki/Subscriber_Identity_Module

Many of us have three SIM cards and swap them into the same phone as needed: (1) International Work-Anywhere, higher-rate, (2) Saudi Prepaid, lowest rate, (3) "Home" country, lowest rate there.