Star Trek: TOS & Reboot
TOS
Ravishment by Starluck -- Kirk/Spock, Mirror Universe. Mirror Universe Kirk takes what he wants and that would be his first officer. A hot and compelling story.
Mindgames by Lady Ra -- Kirk/Spock. Kirk realizes he loves Spock, but Spock is already gone. Is it really too late for them? So in desperation, Kirk goes the only person he knows that can help him: Amanda.
Reboot
You'll Get There in the End (It Just Takes A While) by Seperis -- nu!Kirk/nu!Spock. What if it was Kirk that went into pon farr, not Spock? Seperis explores this special take on pon farr by having Kirk be the one in fever, a result of his meld with Spock!Prime, and how his Spock deals with the news is fascinating to say the least. An original concept on an old fandom cliche.