One of the best tools is disconnecting from the internet. This pins my mental compute on the issue at hand and prevents mental threads from even being created. Need something about a specific library? I have its docs on my machine. Don't have docs? I have its code. No search engine, no Stack Overflow, no Wikipedia. Think harder.
Disable WiFi.
The code might not be optimal, but it's unlikely it would have been by looking things up online in the first place for a prototype/poc. Get prototype done, refine later on second pass.
Mail client, browser, and Slack are killed since they have no reason to live.
Slack is killed because it still has a blue dot from a message on a workspace somewhere. I refuse to fight it for my attention by tweaking notification parameters that don't seem to work. I had tried overwriting `slack-taskbar-highlight.` and `slack-taskbar-unread.` with `slack-taskbar-rest.*`, but it recreates them, and for that reason, killing Slack even offline gives me respite.
Toying with it: unplugging the charger and implementing a feature on battery. Long battery life? Not if you have NVIDIA graphics card activated.