Space Duck

WHY just another Delay/Reverb plugin...you could think.
But give it a try, you can achieve complex and unique results very quick with just one plugin.
Like the most 2getheraudio plugins it has a very nice GUI and a well thought out workflow.
Also check out their other plugins, like RE4ORM, RE4ORM FX (one of my favorite fx plugins ever) G8ATOR
or the legendary free Cheeze Machine!