NetDirectBargains via eBay offers the Mophie Juice Pack Air for iPhone 3G and 3GS in Purple, Red, or White, model no. JPA-IP3G, for $9.99. With free shipping, that's a buck under our mention from four weeks ago and the lowest total price we could find by $1, although many merchants charge over $20. This battery pack and case purports to add 4.5 hours of talk time and features a standby/charging toggle switch, USB micro cable, status LED, and more.

Of note, the original packaging may be damaged or missing, but this is a new, unused item with a 14-day NetDirectBargains warranty.