I bought some contraption Stanley made years ago and it's double purpose, used one way joist with twists can be twisted straight before permenately attaching. Then flip the end around and you can use it against bowed deck boards to seat them up tight to the previously laid board. Works like a champ and the times I pull it out homies always ask what it is, once they see it in action they're amazed for some reason LOL!!
I dont use it much, but when I'm forced to get it out the $30 I paid for it is paying for itself that particular time so it's been paid for a loooong time ago