So many cards in Magic are worth a little, but not enough to put on Page One of the binder. I'm talking things like Seraph, Storm Cauldron, Lin-Sivvi and the like. Around here, we call them "bulk+" It means that they're a little better than truly 10-cent bulk rares, but they're kind of a pain to get rid of through trading. If someone wanted a Seraph, I'd be inclined to just give it to them as a throw-in with a trade!
Fortunately, they're easy to get rid of on a buylist. If you use Trader Tools, you can efficiently get rid of cards in this bulk+ category, since you're scanning a bunch of different stores at once. With a pile like this, you can make a list and then siphon off cards when you're putting together another buylist order - or you can ship them all for a serious amount.
For instance, check out this list that Kelly made of real bulk+ in his collection. All those tables are sortable. You can click on the column name and it'll sort from high-low or the reverse if you click it again. If you go down to the bottom, you'll see the total buylist price and the total sell price.
A bunch of the cards buylist for nothing right now. That's fine, because it costs you nothing to keep a list going. Periodically, a store will need another copy of Dwarven Ruins and you'll have that information at hand. This 240-odd collection of cards can buylist for $35 at the time of writing, which is not bad at all. Adding cards by the hundred takes no time at all with Trader Tools and with the one-click cart fulfillment through Trade Routes (a part of Trader Tools) it takes no time at all to populate your buylist on a site. That's about an hour or less of work, mining your binder and bulk boxes. Not bad!