The Laguerre Filter was created by John Ehlers (Cybernetic Analysis For Stocks And Futures pg 216) and this indicator works well with letting you know both the short and long term trend as well as a pretty good moving average. If the indicator line is above the black line then it is a long term uptrend and below the black line is a long term downtrend. Buy when the indicator line is green and sell when it turns red.
Let me know if there are other scripts you would like to see me publish or if you want something custom done!