@PCBASICBot is made by @KaySavetz. They took inspiration from @BBCMicroBot (which does a similar thing but with an emulated BBC Micro, a computer that was popular in the United Kingdom.) Kay also maintains Atari8BitBot and AppleIIBot.
The bot runs on a Raspberry Pi in Kay’s basement. A Python script checks Twitter every two minutes for incoming tweets directed at @BASICPCBot, and imports them into the appropriate emulator. ffmpeg records the emulator’s output as a video, then the script uploads that video to Twitter as a reply to you.
The code that runs the bot is at https://github.com/savetz/PCBASICBot.
Kay is co-host of ANTIC: The Atari 8-Bit Podcast, where they have interviewed hundreds of people who did interesting things with Atari computers. They are also half of Eaten By A Grue, a podcast where they have played every single Infocom text adventure game.
Also try your hand at our friend, BBCMicroBot.
For more adventures in constrained programming of microcomputers, check out BASIC10Liners, an annual competition to create games in just 10 lines of BASIC code, on your choice of ancient microcomputer. After trying your hand at maximum 280-character code with the this bot, 10 lines will feel like a luxury!