My C64 Emulator, developed in 1993 when I was not aware of the existence of other emulators (AFAIK only the glorious C64S).
Little details:
I wrote the original emulator in Turbo Pascal 7.0 and I have ported it to C++ only recently, just for fun. At the time I told myself, what happens if I emulate the 6510 and have it run the basic ROM and the Kernal? Maybe emulating the VIC a little bit (text mode)? So I made my C64 emulator. At first, it didn't work because I had failed to emulate some instructions (I set the CPU flags badly), but after fixing it... the legendary blue screen appeared! But there was no cursor... I had to implement the interrupt! And once done, the cursor appeared flashing. Next step the keyboard. And then? And then I stopped, I didn't have much time, or enough information to emulate the VIC in a decent way. At the time I had not even the Internet connection.
Now I have ported it to C++ (after 26 years) and I was excited to see it working again!