GPU/Processing

A powerful gaming GPU is a wonder of parallel computing. It can be repurposed for very complex mathematical calculations.

Install from Repositories
It would be best to install it from the Debian repositories.

oclHashCat
Historically, GPUs were used for Bitcoin mining, which is effectively calculating tons of hashes. Thus, apply the same idea to password cracking.

Waifu2x
Use Akropolites and it's unused Nvidia GPU to process and upscale tons of animu images from my collection.

https://github.com/nagadomi/waifu2x