Okay, it's not really a trick, but it's a service many don't know about, or they don't know about the best options. I use snapnames.com and I have put in pending orders with about 100 domains related to my niches. When they expire, I snatch them up, and very rarely is anyone else bidding. The price is high, $59 minimum, but you get a chanced to get a very good EMD that is aged. I've successfully got 3 EMD with keyword exact search for each one is 15k+ per month. The only problem is that they only have a deal with some of the registars. The ones they have a deal with, when you get the expired domain, it is simply transfered over. But some of the other registars the domain actually expires and you lose the domain age.