21.   Auction sites will kick sellers off if it can be determined that they are misrepresenting their products or not sending the merchandise.

22.   Auction sites generally require the visitor to sign in and provide a credit card number.

23.   Besides straightforward Internet textbook sellers, eBay-style auction sites where students can buy and sell used books are also springing up.

24.   A rare trilobite can fetch sky-high prices in Western fossil boutiques or on Internet auction sites.

25.   A Manhattan cabdriver whose fares Wednesday included a man from Collectingnation.com, an online auction site that specializes in Beanies, found himself on a shopping spree.

26.   A potentially bigger obstacle is that the auction site seems to have the cooperation of only a few domestic airlines.

27.   A visitor looking for an item can see prices at several auction sites at the same time, without having to visit each site separately.

28.   All the sites, except Swap.com, allow for ratings, similar to the participant ratings at eBay and other auction sites.

29.   But analysts said competitors will be hard-pressed to catch eBay, which already has a commanding lead over auction sites run by Amazon.com and Yahoo.

30.   But as auction sites look to cash in on the trend by selling more costly goods, this Internet utopia is coming under threat.