I just read one of the best domaining tips I have seen in a long time. It was posted by Jamie Zoch on his blog dotweekly.com which is, without a doubt, one of my favourite domaining blogs. You can read the whole article there, or read my shortened version here:
You probably already know the Godaddy domain aftermarket, formerly known as TDNAM. There you can sort the expiring domains list by traffic and price. Godaddy automatically prices their expiring domains by quality, so if a domain is already generating money as a Godaddy parked page it will be priced with a higher starting bid. Often this starting bid is way overpriced and the domain will expire without any bids. When this happen the domain will go through the same process as other expiring domains at other registrars and often you will be able to hand register these names the instant they drop. That way you will be able to buy domains that are likely to pay for the registration fee in a short time frame.
Very nice tip Jamie, thanks!