Often I need to kill firefox.exe so I've identified this simple way of finding it without having to sort alphabetically and scroll all the way down through reams of pointless, resource-sapping Windows processes (which are no doubt running "just in case" to shave 1 microsecond off an app I use every once 3 years... acrotray.exe, you know who you are). Anyway, here it is:

• Open task manager
• Sort by memory usage
• It's the stupid bloated fat memory leaking process at the top (but double-check it's not photoshop.exe)
• Kill kill kill

Hopefully this will be useful to someone else who also has their system ground to a halt just because they've left their browser on the same 40k static page for more than an hour.