Old Hickory Credit Union is listing a 5.20% APY 18-month share certificate. The minimum deposit is $2,000. The rate table (pdf) is available at this page. I just called and verified that this rate is still available. The CSR did not know how long this would last. The rate sheet has a 1/25/08 date.
Membership is open to those who live or work in the counties of Davidson, Sumner, Robertson, or Wilson or in the communities of Smyrna and Lavergne. You can also be eligible via Select Employee Groups. Please refer to their Membership page for more details. Membership requires a minimum deposit of $25 in the primary savings account.
Branches are located in Nashville, Greenbrier, Hendersonville, Goodlettsville, Lebanon and Old Hickory, TN. The credit union is federally insured by the NCUA (Charter # 67982). It has $136.5 million in assets and 23,650 members.