Foreigner
British workplace slang for unofficial side work using company resources
Common British slang for unofficial work, often making use of company equipment/ time/ premises but solely for personal gain, unrelated to the interests of the company and/or tax department. This phrase is short for 'Foreigner Bashing,' for reasons unknown, but DOES NOT hold racist connotations in this context. With notable exceptions, doing Foreigners is a fairly accepted part of British working life and, depending on the workplace, can even be done with managemental consent.
I'm not coming to the pub this lunchtime, I'm staying at work to do a Foreigner for a mate of mine.