On areas of overlap between Computer Science and Economics
There is a large and thriving community studying what is commonly known as Economics and Computation. This includes 


Algorithmic Game Theory: the study of computational strategic agents. A good reference for this is the seminal Algorithmic Game Theory book. This subfield includes routing games (how selfish agents behave in network routing), mechanism design (auctions, such as spectrum auctions or Google ad auctions) and more.
Computational Fair Division: fair allocation of divisible/indivisible goods. This includes matching markets (college admissions, kidney exchanges) and assignment problems (course allocation, public housing assignment)
Computational Social Choice: efficient aggregation of opinions. This includes standard voting analysis as well as multi winner elections, opinion dynamics and more.