The time_point representing the current time. time_point is a member type, defined as an alias of time_point<high_resolution_clock>.
Slammer (also known as Sapphire, Helkern or SQLExp) was a worm that appeared in 2003 January and was the fastest-spreading worm of its time. The worm was an extremely simple piece of code and its payload was an unintended byproduct of its spreading ability.
Slam dunk is a sports metaphor exactly as the previous responses explain. However, In this case there is additional context that gives this particular usage additional meaning. When President George W. Bush was considering the invasion of Iraq, he asked his subordinates how certain they were that Iraq had weapons of mass destruction.