typo
export to window in browser
sync
playground working draft
fix width
add default code
remove extra newlines
preselect the default code

to reduce the time needed to start the actual playing
don't break mysteriously on undefined input
use code mirror for code and output as Opal does :)
pretty print JSON
readable CM config
scroll the growing result with full-page scroll
save code between page loads
protect from infinite crash on giant code amounts
sync