Circuit City offers the Antec 3.5" USB 2.0 Aluminum External Hard Drive Enclosure (pictured), model no. MX100, for $19.99. Apply coupon code "8MAJTZLA9L" to cut it to $17.99. Shipping costs $3.99, or choose in-store pickup. Even with shipping, it's the lowest total price we've seen for this enclosure without rebate hassles. Sales tax is added where applicable. It supports Serial ATA hard drives up to 1TB. Deal ends July 26.
More 3.5" external enclosure deals, both for SATA hard drives and with free shipping: