A payday loans boss from south Wales paid hackers to launch cyber attacks against business rivals and a consumer complaints group.
A US secret service investigation uncovered the sabotage plots by James Frazer-Mann, Cardiff Crown Court heard.
Frazer-Mann, 35, from Barry, Vale of Glamorgan, admitted five charges of commissioning attacks.
He was handed a four-month suspended prison sentence, and ordered to carry out 180 hours of unpaid work.
The court was told that Frazer-Mann had been described as a "predator" online by customers of his short-term loans firm, Elite Loans.
Complaints about his operation were discussed in an online chat forum run by Consumer Action Group.
"He offered a hacker $100 (£80) to take a consumer website down," said prosecutor James Davies.
"He also made payments to another to orchestrate attacks against his competitors."
Overseas cash trail
The court was told that payments of £2,000 were made to two computer hackers, through a payment system based in Costa Rica, to launch what are known as "Denial of Service" attacks on other payday loan companies.
"The effects of such attacks are significant as the companies are so reliant on their websites to generate business," said the prosecutor.
But Frazer-Mann's activities came to the attention of the FBI when they closed down the hackers' payment websites in 2013.
They found evidence of cash transactions linking the south Wales defendant to the hackers, and tipped off the National Crime Agency.
It led to the businessman's home in Barry being raided by cyber crime officers from Tarian - the southern Wales regional organised crime unit.
Mr Davies added: "He claims his company had initially been targeted by other companies. It's an area of business which is highly competitive and some use unethical practices."
Frazer-Mann pleaded guilty to five counts of commissioning or encouraging offences which prevent access to programmes or documents held in a computer.
Sentencing him, Recorder of Cardiff Judge Eleri Rees said: "Over a period of two years you resorted through revenge to try and disrupt websites.
"You were prepared to spend quite considerable amounts of money to achieve this end."
The firm Elite Loans has since ceased trading, and Frazer-Mann now works as a carpet cleaner.
Speaking after the hearing, the founder of Consumer Action Group Marc Gander said: "This shows the lengths these payday loans companies will go to in a bid to silence their critics.
"He was upset and contacted a hacker in the US. But it was a very stupid thing to do and it failed to work."
Responding to the sentence, Det Insp Paul Peters from the Tarian cyber crime unit said: "Criminal activity conducted online can have far reaching effects on businesses and individuals across the world.
"This case illustrates our commitment to identify and bring to justice those who commit offences online."