If it sounds familiar, well, it is, and the NYT has a nice set of articles (overview, interview with hostage, photos) commemorating the anniversary. Among the links therein is the Life Magazine article which formed the basis for Sidney Lumet's masterful film:
“If they had been my houseguests on a Saturday night, it would have been hilarious,” Shirley Ball recalls. “Especially with John’s antics, the way he hopped around all over the place, the way he talked. John called me ‘mouth’ because I was the talkative one. It was, ‘Hey, mouth, do this’ and ‘Hey, mouth, do that.’ I really liked them both. They tried to be nice—except when they were cornered. Such aboveboard guys, they even told us they would kill us if they had to.”
“I’m supposed to hate you guys, but I’ve had more laughs tonight than I’ve had in weeks,” bank manager Barret tells John Wojtowicz.