2D joint editors
A seamless editor extension for Unity which gives you very intuitive handles for editing 2d joints. A must have if you do any work involving 2d joints. Made By Firtina Ozbalikci.
Get it from Firtina's github, here:
This is probably the best integrated asset I've ever tried for Unity. You just put it in your project and it works automagically - no components, no nothing. And it looks and feels like it should have always been there. I haven't actually used any editor extensions before and this may just be how they work, but it's completely free and completely awesome so there's no reason not to use it.
You can read more about this asset came to be on Firtina's blog, here: