Yes! PLATO still has active users and may be accessed over the Internet. Go to Cyber1 to learn more.
Brian Dear at The Friendly Orange Glow has been researching PLATO's contributions with intent to publish a book.
David Woolley has an excellent overview of PLATO at PLATO: The Emergence of Online Community.
See the The PLATO History.org website is the home of the PLATO History Foundation and the archive for information about the history and significance of the PLATO computer system and its online community.
The Foundation's principal focus is to advance the public awareness of the history, significance, and importance of the PLATO computer system and its online community, and to tell the story of the people who designed, built, and used the system.
See the article from 1997 about the PLATO-fest where they held Empire tournaments.
Also the December 2008 issue with Ray Ozzie, Microsoft's Chief Software Architect.
Back to 1984 Antic Magazine article titled PLATO Rising, about the development of the PLATO cartridge for the Atari.
PLATO Learning
provides a lineage from the original PLATO for learning online today.