Gain more program memory with the Arduino Nano

Arduino Nano with ATmega328P is available in two variants: "ATmega328P" and the older "ATmega328P (Old Bootloader)". The newer variant uses an optimized bootloader which has double upload transfer speed and only needs 512 bytes instead of 2048 bytes. Unfortunately the saved space cannot be used as additonal program memory for sketches. But this pity can easily be changed to gain more program memory with the Arduino Nano.