For a long time i've not seen this, maybe just because i didnt used auctions for some time.
Here's classic Ebay cheating: inflate of the price.
Actuallyu this is very usual fraud when seller use secondary account or friends account to raise pprices on own items. But i found one very stupid seller who did that wih 100% of his items. SO we are welcome seller from Russian federation: deviladriver.
He has 100% feedback rating (mostly buyers rating), not so mush feedbacks as seller. At the moment when i fixed him he got 124 items on auction and a bit more before i fixed it (about 150), but they already ended.
I found this seller by automatic Goods search tool, there was some interesting item and i decided to watch and bid on it at the end of auction. Right before ending of te item i found that it has few low bids and decided to bid. But in the seconds before end price was raised up to next step over my bid, however i put high bid, and i lost it.
After that I decoded to check buyer who got highest bid, and there was surprise!
This buyer (with feedback rating - 4) made bids on 76 items of this seller! And in total he makes bids only on this seller because his relations with seller was 100%. He was very hard bidder - 225 bids on 76 items from only one seller! However he could be just fan of this seller, because he already bought several items before.
I decided to explore all other items from this seller. And what i found? This fan won almost all items from this seller! He's very lucky fan!