This post discusses the Leviathan DLC pack for Mass Effect 3 - see the video below
And here are the War Assets gained by completing this mission.
The Following are War Assets gained by exploring the galaxy in search of Leviathan
Liquid Assets - A group of influential business leaders are contributing financially to the War Effort and, though they don't know it, funding the construction of the Crucible.
Dextro Rations - Luxury food items suitable for Turians and Quarians provide a morale boost for troops about to go into battle
Husk Neural Map - Studies made of Husk brain patterns aid the fight against Reaper troops
(there are more available through new systems uploaded in the pack but these are the ones I found while playing the mission)
The following are War Assets gained by finding the Leviathans
Dr Ann Bryson - here research into ancient technology is invaluable to the Crucible's construction
Leviathan Enthrallment Teams - Highly trained commandos deploy Leviathan devices behind enemy lines to turn Reaper forces against each other and slow their advance across the galaxy.