Hittime_SG via eBay offers this GPS Bluetooth 4.0 Tracker for $2.30 with free shipping. That's tied with last week's mention as the lowest total price we've seen. (It's the best price now by $6, outside of other eBay sellers.) It can be attached to an item so that it can be located within a 75-foot range via your iPhone or Android smartphone.
Note: This item ships from Hong Kong and may take two to eight weeks to arrive.