The symbol 2K is equal to the symbols K2, KK, and 11:11. This is because they can all be read as the letter K, which is the 11th letter in the English language. 2K can mean 2,000 when K is taken as shorthand for 1,000. In this way the symbol 2K was used to indicate the millenial new year of the year 2,000, or Y2K.
2K in Popular Culture
In End of Days, the setting for the movie takes place shortly before and during the Y2K new years, and there are posters for Y2K all around the city.
In Strange Days, the setting is new years 2000, and the acronym Y2K can be heard several times.
In Stay Tuned, John Ritter and Pam Dawber wear jumpsuits with large golden K's on them, making the pair into a 2K symbol. John Ritter also died on September 11th, 2003, which is an anniversary of the September 11th event which has been connected to the letter K through the number 11, and also to the 2012 alignment which happens at 11:11 AM. Both September 11th and December 21, 2012 have been connected as possible catalysts for enlightenment.