Japan to tighten regulations on high-frequency traders

Better still. Get rid of Central banks especially the IMF and fractional reserve banking. Oh and money printing, QE.

You could just place higher transaction fee in which will become a speed bump to all computerized transaction since they all calculate cost vs profit in which cost is higher to profit the computers will not make transaction.

Adding a random delay to all trades is a good idea and will put a stop to these leeches.

Most of these traders are not long term investors (don't hold stock for longer than a few minutes/hours to a day) = they become useful idiots to the bigger players like hedge funds and help drive volatility. Most likely all stock transactions should have a 100-200Yen surcharge added -even for the brokerages (this means everyone). = the extra fee would greatly reduce volatility and force people to hold financial assets longer.

Those with the best tech make the money......