4 ms·

And this was possible (in the 90's!) with good old ICQ...

• freakwit 16y ago
  http://en.wikipedia.org/wiki/Talk_%28software%29 http://en.wikipedia.org/wiki/Talk_%28software%29 1983 with talk. Anybody got anything earlier?
  • Groxx 16y ago
    1893: peeking over someone's shoulder as they use a typewriter to write you a letter.
  • ericflo 16y ago
    If this were Convore, I would star Groxx's message :)