Tennessee's annual sales tax holidayruns August 2 - 4 this year, and shoppers are expected to save between $8 and $10 million on items like clothing, school supplies and computers. For computer sales in Tennessee, these are even bigger sales days than Black Friday. These weekends are touted as economic boost for Tennessee and tax relief for low-income families, but a nonprofit research group, the Tax Foundation, says these tax holidays may not actually do much for the economy.