Tweet-sized syntax highlighter.
Only work works in Webkit, because it exploits the fact that id's become global variables.
The editor will highlight element properties, try entering 'body.style.background = "#000";'.
b[t='innerHTML']='<hr id=y><p id=z contenteditable>';f='y[t]=z[t]';for(p in b)f+='.replace(/'+p+'/ig,"<b>$&</b>")';z.onkeyup=eval.bind(b,f)