Have you ever had to reduce the flow from your filter?

Have you ever had a filter that even on the lowest setting, that it was just far too strong for your tank setup/layout? What did you do in order to reduce the flow, or make sure that it wasn't just directed at a given specific point that would toss fish around inside of the tank?

Was your method something of a DIY with household items, or were you able to purchase something that fit your filter which was able to disperse the water output?