[gregwilliams]

I was recently told that, "if you turn dialing from the home screen off, you can lock the keyboard/device by pressing the letter K". Is that true? If so, how do I turn off home screen dialing?

[kasperapd]

It is true. Press the green send key to get into the phone menu, then press the menu button, go to Options > General Options > Dial from home screen > No

[anon(153966)]

Plus many other tips / shortcuts like that can be found, here.