Create an image that depicts rubbish - it should include things that are typically considered to be rubbish (eg. things that is or broken, food scraps, packaging)
It can be rubbish presented in any form; a pile of rubbish, a rubbish monster, an entire city made from rubbish etc...
Also, check out this great piece by Larwick as possible inspiration.
Canvas Size - Unrestricted.
Colours - Max 20.
Transparency - Optional.
Animation - Optional.