ChubbiesTech via eBay offers the refurbished Unlocked Apple iPhone 4 8GB Smartphone in Black for $183.95 with free shipping. That's a $46 under our mention of a new unit from last week and it's the best price we've ever seen for an unlocked version of this phone. (It's also $111 under the best price we could find for a new unit.)
Note that no warranty information is given.
What are you doing for fun that you could also do for money? Here are some ideas to get you thinking, and tips to get you started.