Optiboot (an older version) is installed by default on the Arduino Uno and (as of 2018) official Arduino Nano boards. It can be installed on all older mega8, 168 or 328 based Arduinos. As of 2019, ...
Here's the new description with all links and additional text removed: Order your pcb design at JLCPCB: $2 for 10pcs PCBs (24 ...