INCOMPLETE
Parity
Parity is an Ethereum client, written from the ground-up for correctness-verifiability, modularisation, low-footprint and high-performance. It utilities the Rust Rust programming language, a hybrid imperative/OO/functional language with an emphasis on efficiency. You will find here a chart showing the efficiency of this client compared to geth or eth.Parity is professionally developed by Ethcore.
As pointed by Vitalik Buterin in this twit, it is highly recommended to connect to Ethereum with this client, especially with minimum version number 1.2. It seems Parity is gaining traction among the community and may become the upstream ethereum client.
Parity runs on Linux, Mac OS and windows.
Build and install
You can build parity from source following these instructions and this tutorial from Ethcore. You may too install binaries if your Linux distribution have such a package. Please visit the parity page on Ethcore to download binaries or a Docker image. Archlinux users will find two packages in the AUR repository. The build and installation should normally go smooth if your machine is up to date and correctly setup.
Once the package is installed, run $ parity -v
to check the installation went fine. The command shall return the installed version and the license.
Configuration
There is no man page but you can run $ partity --help
to see a list of options and default settings. You will see that configuration settings are stored in the~/.parityfolder.
Key management
Geth
Eth