Saw this 46-year old on a bot team, oldest I've noticed yet:
http://www.buzzerbeater.com/player/21775012/overview.aspx
That makes him older than the oldest-ever NBA player, Nat Hickey who played one game in the 1947-1948 season at 45 years, 363 days (he was the team's coach).
Kevin Willis played at 44 years, 224 days in 2007
Robert Parish, Hall of Famer, was 43 years, 254 days
and Dikembe Mutombo, THE BIG FINGER WAG, played his last game at 42 years, 300 days.