Go to https://treasurydirect.gov/savings-bonds/i-bonds/ but read the terms carefully. The interest rate is ~10% for 6 months, but you lose 3 months of interest (or something) if you cash the bond in prior to 5 years (or something-- don't rely on what I'm saying here-- read for yourself), so it might not be as good a deal as it seems. The bond is "inflation indexed" so, if inflation decreases, the return after 6 months will go down.