High Yield Investment Program.
A synonym for typically Internet-based ponzi
schemes, with small minimums (typically less than US$500) and promised sky high returns without risk (i.e. more than 20% per year).
NOTE: See Triumph of the Optimists: 101 Years of Global Investment Returns
by Elroy Dimson, Paul Marsh and Mike Staunton.
Remember that new HYIP that I found that pays 25% a month? Well it paid for three months and then it collapsed.