hm... maybe a method that makes an screenshots and saves it as an sprite in some run-time created object or variable or whatever they're called now, where you can resize, and change any parameter just like with any other sprite/entity? It would be useful not only for this, but for special effects, like motion blur, "drunken" effects... but I don't know about the performance of the engine when it comes to taking screenshots, so I don't know if it's possible...