Units

P - Probe

Z - Zealot
D - Dragoon
T - High Templar
K - Dark Templar

S - Shuttle
V - Reaver
O - Observer

S - Scout
C - Carrier
A - Arbiter
O - Corsair

Buildings

B - Basic Structure.

Then...

N - Nexus.
P - Build Pylon.
A - Assimilator.
G - Gateway.
F - Forge.
C - Photon Cannon.
Y - Cybernetics Core.
B - Shield Battery.

V - Advanced Structures.

Then....

R - Robotics Facility.
S - Stargate.
C - Citadel of Adun.
B - Robotics Support Bay.
F - Fleet Beacon.
T - Templar Archives.
O - Observatory.
A - Arbiter Tribunal.

Special Abilities

T - Psionic Storm (Templar).
L - Hallucination (Templar).
R - Recall (Arbiter).
T - Stasis Field (Arbiter).
D - Disruption Web (Corsair).
F - Feedback (Dark Archon).
C - Mind Control (Dark Archon).
E - Maelstrom (Dark Archon).

Other

L - Load (Shuttles).
U - UnLoad (Shuttles).
R - Recharge Shields (Shield Batteries).
I - Build Interceptors (Carriers).
R - Build Scarabs (Reavers).

Upgrades

Forge
W - Ground Weapons.
A - Ground Armor.
S - Plasma Shields.

Cybernetics Core

W - Air Weapons.
A - Air Armor.
S - Develop Singularity Charge.

Citadel of Adun

L - Develop Leg Enhancements.

Robotics Support Bay

S - Scarab Damage.
C - Increase Reaver Capacity.
G - Gravitic Drive (Shuttles).

Templar Archives

P - Psionic Storm.
H - Hallucination.
K - Khaydarin Amulet.
M - Mind Control.
E - Maelstrom.
T - Argus Talisman.

Fleet Beacon

A - Apial Sensors.
G - Gravitic Thrusters.
C - Increase Carrier Capacity.
D - Disruption Web.
J - Argus Jewel.

Observatory

G - Gravitic Booster.
S - Sensor Array.

Arbiter Tribunal

R - Recall.
S - Stasis Field.
K - Khaydarin Core.