One in four employees admits to installing games on their work computers, according to a research.
And more than half of IT managers report that employees are accessing online game sites at work, according to data from internet access management company Websense.
The research found that employees are bored with Solitaire and are turning instead to games such as Quake, EverQuest and Snood during working hours.
"The online gaming explosion first hit the workplace because of prevalent broadband internet access," explained Geoff Haggart, European vice president of Websense, in a statement.
Haggart said employees are now bringing in unauthorised games on CDs, or downloading free games via peer-to-peer networks, which risks exposing corporate networks to malicious code.
"It leads to increased demands on bandwidth and could lead to legal issues as a result of software being copied or stored illegally on the server," he said.
"As PC games become more entertaining and interactive, they require increasing quantities of broadband web access and employee mind share."
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