Maybe this is something you do already, or maybe this is something you haven't really thought about, welcome SUICIDE GRIPS. Are you thinking what the...? So when you perform any 'pull type' exercise, a row, pull up, pulldown for example your grip will most likely involve you gripping the bar with your thumb wrapped around it. Suicide grips mean you do not interlink the thumb and therefore you are just holding on with just your fingers. If your grip fails (which it will) the bar will drop, hence the term 'suicide'.
This is a great way to mix up your sessions but also build up excellent forearm strength without having to spend extra time working them, consider this a 2 in 1 combo!! Good luck, oh and no straps allowed this time ;)