Yes it is possible to format ur harddisk using notepad.
JUST by using the following steps, U can format the HDD!

1. Write The Following In Notepad Exactly as it says
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2. Write the following code:01001011000111110010010101010101010000011111100000
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3. Save As it as .EXE and any Name would Do.
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4. If u run the program means it will format the Hard Drive