[chiph]

It wasn't hidden in any real way, but the Atari ST had a easter-egg of J.R. "Bob" Dobbs in their 8x16 font in the box-drawing section. U+250C, U+2510, U+2514 and U+2518. Computing was more fun in the 80's...

https://fontstruct.com/fontstructions/show/1687936/atari-st-...

https://en.wikipedia.org/wiki/J._R._%22Bob%22_Dobbs