A is for Archer. Jonathan Archer.
B is for Blalock's Boobs
C is for Columbia, the NX-02
D is for Dastardly Xindi Plan to destroy the Earth
E is for ECS Horizon
F is for Fleet of Starships, like some kind of Star Fleet
G is for the goo that Trip gets to spread all over T'Pol in the decon chamber.
H is for Hoshi Sato
I is for Insectoid Xindi
J is for Jazz, which made T'Pol feel invigorated
K is for Kalen Archer, one of Archer's descendants in the "E2" timeline
L is for Lorian, one of T'Pol's descendants in the same timeline
M is for MACOs
N is for Nausicaan pirates
O is for Orion slave traders
P is for photonic torpedos.
Q is for Quantum dating
R is for Romulan minefield
S is for Surak
T is for Trip
U is for Unexpected