Walmart offers the SanDisk 128GB Ultra Class 10 microSDXC Memory Card for $19.50. Opt for in-store pickup to avoid the $5.99 shipping charge. That's pennies under our mention from a month ago and the best price we could find by $4. It includes an SDHC/SDXC adapter and features read speeds of up to 80MB/s.
Retailers mark up products by hundreds of times their cost — but you don't have to pay the premium.