Meritline offers its Mini Wireless Bluetooth v2.0 USB 2.0 Adapter for $2.99. Coupon code "MLCKP03BNL1" cuts it to 95 cents. With free shipping, that's the lowest total price we could find for a similar adapter by a buck, outside of the mention below. (It's also pennies more than our June mention of a similar item.) Coupon expires after 300 uses.

Expect this item to take two to three weeks to arrive.

A close price: Several sellers at eBay charge around $1 for similar adapters.