I like to stick to mostly default UI as much as I can but I wanted something to separate my debuffs from the target panel and maybe make them a bit bigger in their own little area while still leaving everyone else's debuff in the normal position below the target frame, sort of like this quick mock up I made real quick, please excuse the really crappy MS Paint cropping and scaling.
I have found quite a few like it but with some issues. Most use bars for the debuffs, where I would prefer an icon. Some also grab all the debuffs, meaning mine still end up grouped in with everyone else's.
I would also rather not use something like TellMeWhen or Auras as I would like this to mainly be a quick "Here's the box where you debuffs show" rather than having to set up every single debuff individually for all my characters.