I just got this in my email,, and it was interesting enough to post this on the 'General Forum" here as it is within the guidelines of Invelos.. Its Cell phone tips and I have never seen these before. I'm sure  it's making the rounds now on the Internet, but was going to post them here if you care to take a gander and give us an idea if these tips are bogus or not. and what communication service you are currently using.
I'm on Telus and Rogers mobility so I will be trying these out this weekend.
Terry   

THINGS YOU NEVER KNEW YOUR CELL PHONE COULD DO.

There are a few things that can be done in times of grave emergencies.
Your mobile phone can actually be a life saver or an emergency tool for
survival. Check out the things that you can do with it:

FIRST

Subject: Emergency

The Emergency Number worldwide for Mobile is 112.

If you find yourself out of the coverage area of your mobile;
network and there is an emergency, dial 112 and the mobile
will search any existing network to establish the emergency
number for you, and interestingly this number 112 can be dialed
even if the keypad is locked. Try it out.

SECOND

Subject: Have you locked your keys in the car?

Does your car have remote keyless entry? This may come in
handy someday. Good reason to own a cell phone: If you lock
your keys in the car and the spare keys are at home, call someone
at home on their cell phone from your cell phone. Hold your cell phone
about a foot from your car door and have the person at your home press
the unlock button, holding it near the mobile phone on their end.

Your car will unlock. Saves someone from having to drive your keys to you.

Distance is no object. You could be hundreds of miles away, and if you can
reach someone who has the other 'remote' for your car, you can unlock
the doors (or the trunk).
Editor's Note: It works fine! We tried it out and it unlocked our car over
a cell phone!'

THIRD

Subject: Hidden Battery Power

Imagine your cell battery is very low. To activate, press the keys *3370# .
Your cell will restart with this reserve and the instrument will show a
50% increase in battery. This reserve will get charged when you charge your cell next time.

FOURTH

How to disable a STOLEN mobile phone?

To check your Mobile phone's serial number, key in the following
digits on your phone: * # 0 6 #

A 15 digit code will appear on the screen. This number is unique
to your handset. Write it down and keep it somewhere safe.
When your phone get stolen, you can phone your service provider
and give them this code.
They will then be able to block your handset so even if the thief changes
the SIM card, your phone will be totally useless.
You probably won't get your phone back, but at least you know that whoever
stole it can't use/sell it either.
If everybody does this, there would be no point in people stealing mobile
phones.

And Finally....

FIFTH

Cell phone companies are charging us $1 .00 to $1.75 or more for 411
information
calls when they don't have to.

Most of us do not carry a telephone directory in our vehicle, which makes
this
situation even more of a problem. When you need to use the 411
information option,
simply dial: (800) FREE 411, or (800) 373-3411 without incurring any charge
at all.
Program this into your cell phone now.

This is the kind of information people don't mind receiving, so pass it on
to your family and friends.

Quoting Lopek:

Quote:

This will be a manufacturer specific functionality if it is true - which I would doubt. Why would you have a hidden reserve??? 

One of the HP Ipaq's had a feature that would reserve some battery power when it ran down too far. It wouldn't allow you to power it back on until it was in the cradle for a while, so the data could be protected. It didn't really work; they usuall wouldn't come back on at all without a hard reset or warranty repair.

However, I doubt this has ever been used or needed on a phone.

I never trust pages of handy tips that end with a phone number! Free? Maybe, but someones getting paid.

I use 1-800-FREE411 all the time and have it on speed dial. It works great. They play an ad before you ask for the listing and before the number is given. ONe thing that I like is if you forgot the number it just gave you. You can call back and hit an option to repeat the last number. and the newest feature is that you can have the number send as an SMS message to you.

I Recommed this service.

Any GSM mobile phone will accept 2 emergency numbers, and will make the call regardless of the network it's on, with the keypad locked or if you have money on the sim card (rechargeable ones) or not.
The numbers are (logically) 112 and 911. It'll check which country it's in and use the appropriate one even if you use the wrong one. Adding to jykke's words. Use it ONLY if needed.

As for IMEI Locking, most of the mobile operators are already maintaining a shared database of blacklisted IMEIs, so it's getting more difficult by the day to find a place where to use a stolen (and reported) mobile phone. It is, however, possible to change the Phone's IMEI with the proper equipment. It's not usual that your typical burglar has access to it, though. The newly coded IMEI will have to be a valid one too, and the networks do detect duplicate numbers and light up the alarms. Change of IMEIs is a criminal offense in most countries.

Power reserve. Not true, sorry. Like someone already noted, it's a code used by some manufacturers that controls the power/protocol of transmission. When entering that code you'll be using a protocol which uses less transmission power, and so saves battery. It'll look like your battery has recharged a little, but what happened is that, with the remaining battery and the new operating conditions, it'll last longer. Like when you use a laptop PC and change to a power saving mode, battery suddenly says it'll last longer than before. Your sound quality will degrade significantly if you use this option in a compatible phone.

Cheers,