Yes, I know this can be common sense but some people probably haven't considered it.
I thank you in advance for your flame posts and would also like to thank whoever shouts repost, if this is a repost feel free to remove it.
Keep in mind this is an 'exploit' TO ANOTHER PLAYER, and you'll probably royally aggravate whoever happens to get caught in your web with this.
Today, I had about 30 of a rare item and knew it would take me AGES to sell them all, and really didn't care enough to maximize my profit on them. I noticed only one other on the Auction House, listed at 2200g, so I posted them all in decreasing value (From 2100g down to 400g each), figuring people would buy one, then someone else the would buy the next eventually. Little did I know there was someone running a bot to "buy low and sell high". In roughly ten minutes I sold all 30 of the item for ~25,000g total. Did I lose some potential profit? Maybe. Did I save myself 30 bag slots that would have been taken for weeks to months? Absolutely.
I'm not saying this 'exploit' works with everything, but I can definitely imagine if you catch yourself with a bunch of something 'rare' that will take you ages to move on the auction house you could give this a whirl and see if any bots are lurking your realms AH. Not guaranteed to work, but when it does it can be mighty profitable. (See screenshot linked at bottom.)
STEPS:
If you can't figure out the method from what I explained above:
1: Stockpile an item that there are very few of on AH (1 or 2 of them up I'd say) that are running at a relatively high price.
2: Post the auctions in decreasing value down to a low price (With the lowest end of your posts still being profitable and worthwhile.)
3: Keep a sum of the item still on hand in case anyone is botting, so you have more bait to throw at them at a higher price.
4: Wait and see if anyone happens to be botting, if they are, try and figure out their pattern (Such as profit more than 1000g, don't spend more than 999g, etc.)
5: If auctions sell, keep posting them while watching their pattern (In my case, the person never spent more than 750g, so I started posting the item at 750g)
6: ???
7: Profit! (Literally)
That's not photoshopped, I just removed names/item used.
Good luck!