OS With custom bootloader, Video memory editor, GDT, DiskReader & Print & CPUID Functions.
Things to add: live memory editor from user input ex: mov al,0x01 int 0x21 mov dl,al ;move the integer entered by the user, into dl
HOW TO COMPILE AND BOOT:
in a console type:
nasm bootloader.asm -f bin -o bootloader.bin
nasm ExtendedProgram.asm -f bin -o ExtendedProgram.bin
copy /b bootloader.bin+ExtendedProgram.bin bootloader.flp
Then, open Boch 
Done!
Enjoy.