addon that predicted eclipse cycles (i'm not crazy)

so back in the day there was an addon (i found out about it during ulduar content) that was able to run the math on crits and if it was for sure going to proc an eclipse way before the native ui would tell you. (ie- you would have a message pop up while casting wrath to start casting starfire immeaditly after.)

I have long since forgotten what this addon was called, but i was hoping someone else knew about it and even possibly dredge up an old copy of it somewhere????

I know im not crazy, it definitly existed and was massive for optimized dps rotations.

please help!