Bottle rockets shoved inside a PVC tube after being lit, have a cap on the back end so you don't get blasted by the exhaust..... You can aim it, sort of.

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[Linked Image from lh6.ggpht.com]
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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).