WPA is WiFi Protected Access - it's the most common method of encryption used to secure a wireless network. If you have a laptop or smartphone and you're trying to connect to a WiFi network, you'll usually need to enter a WPA key (or password) in order to connect to it.
In the live-action adaptations by Sir Peter Jackson, Sauron is portrayed by Benedict Cumberbatch in The Hobbit trilogy (who also portrays Smaug in the same trilogy) and was played by Sala Baker and voiced by Alan Howard in The Lord of the Rings trilogy.
The Sam Scudder version of Mirror Master appears in the third season of The Flash (2014) portrayed by Grey Damon. This version is a metahuman with the ability to travel through mirrors and anything with reflective surfaces (similar to the New 52 version).