One is Napster, an MP3 swapping site that is, in the eyes of the record companies, the equivalent of a vast flea market of stolen goods.
Netcycler, the online swapping site, has seen its UK launch.
It is not a ticket reselling or swapping site, however, but organisers say it may help to prevent touting.
Kids clothes and toys swap site thredUP will now be catering to dads with the launch of a paternity clothing swap.
The Travis singer, Fran Healy, said last year that online song swapping sites were "brilliant".
But what is in it for file-swapping sites like Grokster, eDonkey, or Morpheus?
Some 20 consumer-to-consumer swapping sites opened on the Internet earlier this year, according to e-commerce analysts, with about five of those sites coming to the forefront.
Swapping sites could become as popular as auction sites, Mr. DeBono said, as people become more comfortable assigning values to their unwanted items.
As for smaller companies, like Joe Barter and other exchanges that have fewer business members, he said, "They're only swap sites; they have no supplier network".
But at SwitcHouse, which, with more than two million items listed, is considered one of the largest personal swapping sites, developers would disagree.
To some extent, e-commerce analysts said, swap sites have had to react to eBay's purchase of Half.com, which, with eight million listings of items at half price, cuts into the territory of these various pricing models.
