What the May 6 crash did show was that while high frequency trading may work just fine in normal market conditions, when trouble comes the markets become a mile wide and an inch deep.

FORBES: High Frequency Traders Face SEC/CFTC Panel

The fine, though relatively small, is bound to give more ammunition to the anti-high frequency trading crowd, which is demanding regulators do something to stop this specialized form of computer trading, or at the very least slow it down.

FORBES: Regulator Takes Aim at High Frequency Traders