This has to be one of the best dunks of the year, it was freaking crazy. The shot was actually an attempted buzzer beater by Joe Johnson, but he was off targert. Then Josh Smith came out of nowhere with the game winning dunk at the last second. The Atlanta Hawks secured a spot in the playoffs with that win.
Here's the celebration, and another angle at the end.
Josh Smith had a game winning dunk earlier this season, very similar. The one last night was still better though.