Walmart offers the refurbished Garmin nüvi 52LM 5" Portable GPS Navigation System with Lifetime Maps, model no. 010-01115-01, for $78 with free shipping. That's the lowest total price we could find by $4, although we saw it for $2 less in November. Features include a 5" 480x272 touchscreen LCD, lifetime map updates, voice navigation, lane assist, and microSD card slot.

A 1-year warranty applies, although it's unclear who supplies it.

Update: Even better, BuyDig has it new for $100. Apply coupon code "VMEDEL" and pay via Visa Checkout to drop it to $77. With free shipping, it's $1 below the above mention of a refurbished model.