Radar - Allows increased viewing capacity.
Heavy Bombers - allows for longer range, deadlier strikes and an increase in firepower (up to 8 units).
Nationalism - creates a factory of an additional 2 units placed on the capital at the start of each turn.
Reinforcement - allows reinforcement of ally's capitals
Super Subs - German-specific power; with +10% attack advantage, allows up to 3 units to any Atlantic or Mediterranean sz with the additional ability of being to take ownership of those sea zones.
Industrial Tech - this adds a bonus reinforcement of 3 units to the nation to be placed anywhere where placement is enabled for the nation.
A-bomb - US specific tech; allows an artillery attack of up to 40 units on opposing nation's capitals. Note, UK can use the espionage tech to assist the US in developing the bomb, but it hits at a 50% rate and loses 100% of attacking units.
Espionage - allows an artillery attack of up to 5 units against an Italian/German techs.
Tenacity - this allows the Japanese to have limited unit strikes against their original islands. The 'midnight' express units have high hit/loss rates.
Recruitment - Factory bonus of +1 troops to each of original land territories that is owned.