I must admit, another thing I loved about EEE was the fact that it actually kept track of its own continuity, and it showed, whether it was a little thing like Rolf giving Jonny the yo-yo that he previously gotten from Ed in a trade, or something big like the fact that Double D actually archived his inventions from previous episodes to learn from past mistakes. Such continuity is usually not very common in animated shows like that, so for EEE to do it almost felt like we as viewers were being rewarded for actually paying attention.