...such as modems, GSM Modems, PC-BIOSs, Mobile phones, FAX Machines, etc.
They have an option of resetting all the parameters to factory settings (default settings).
Its just a matter of calling a function to set the settable values to default values and save them in EEPROM. Such as:

void LoadDefaults (void)
{
SetValue1=100;
SetValue2=100;
HighLimit=1000;
LowLimit=0;
...
...
...
SaveToEEPROM ():

return ;
}