There is this little gem on the internet that will help you either a) make you some money or b) give you a good deal on items fround througout your city. I have to thank Nightrunner for introducing this one to me a few years back.
Here is how the slickdeals.net hack works. I only call it a hack because it is basically a short cut to a ton of due diligence! First log in to http://www.slickdeals.net/ There are forums which will have postings of deals all over town. You can basically sift through these deals by going for only the "4 thumbs up" or "5 thumbs up". Look for a deal on a item that you want to buy for yourself or re-sale.
Next, log into http://www.ebay.com/ . To sift through the item you want to buy/re-sale, you'll want to sort through it buy showing the "show cleared items" button. Type in the product and click on this button. It will show you all of the site listings that have cleared or will clear! If your item is more than the intended purchase, congrats, you'll make some money (subject to market demand and liquidity). If you are buying this for yourself, then at this point you are done. For people re-saleing their item, read onward.
The final part of the Slickdeal.net hack is to take the overall amount and find the lowest or next lowest price on ebay (you'll want a quick sale so you can move on to the next product). Afterwards log into http://www.craigslist.org/ and list your item. For quick sales, try to focus mainly on electronics. There is also a newer site http://www.backpage.com/ which happens to link to online newspapers in the area. If you comb through the deals at http://www.slickdeals.net/, it can be a great way to suplement your day job.
For more information regarding this, you can go to either dailymotion or YT, for access to a streaming video tutorial. I will put up a Sam's Club hack later which will apply to electronics.