I have discovered that I can pretty much slow time whenever I want using the Nerd Rage perk + hot keying clothing.
1. First, you need 10 INT to get the nerd rage perk.
2. Then find yourself some clothing that gives and Endurance boost, for example farmhand clothes + sea captain's hat (2+2 = 4 endurance).
3. Damage yourself enough to trigger nerd rage, let someone shoot you until your below 20% health or fall off a short cliff enough times.
4. Now put your endurance boosting clothes on.
From then on your can trigger nerd rage whenever you want just but equipping and unequipping your clothes. Very handy at low levels, you can pretty much just run though anything.