Snow

hahah thou shall feel the warth of the snowing urnal cake particles!
 
The script shouldn't be slowing down your pc, if you want to inspect it, it's at /forum/snow.js

You can block scripts with https://addons.mozilla.org/firefox/722/

The snow is part of the winter theme of the forum. Spring may be more to your liking :)
 
When you're just browsing and not encoding video or some such, you're not really using your cpu.
What's the point in having a cpu if you're not using it?
I say you let the script be and let it use 10-50% of you cpu.
It's not going to have any effect on your overall system performance anyway.