I have thunderstorm on the castsequence like others have mentioned, just moving the comma one spot for each toon ( ,thunderstorm,,,, etc) and it works great for me, every 45 seconds I have 5 'o shi_' buttons. Some have mentioned mixing that in with earth shock, etc on the sequence but I have all my shocks on different hotkeys (I normally only use 5 frost shocks to slow someone, followed by 5 lightnings, dead).