Other People's Money, abbreviated OPM, was a mutual fund started after the uneasiness in the Grantville stock market that followed the death of Guffy Pomeroy. The fund was started almost by accident, after Sarah Wendell of the "Sewing Circle" was overheard mentioning that finding safer ways to invest sounded "like a job for a mutual fund or an investment bank". After that had made a few rounds through the Badenburg rumor mill, it was widely believed that they were definitely planning to start one or the other, or maybe both. That belief was so solid that the fund had to be formed, under the pretense that it had been long planned as a closely-held secret, because the actual truth would not be believed.
The fund's name was a nod to the 1991 movie Other People's Money, a copy of which was owned by the Wendell family. The name also served as a reminder that the fund was in business to invest other people's money.