It is interesting to work for eBay; however, most of the time I am looking at the massive data without really thinking about how they are generated... for instance, I have no idea how difficult it should be to be a successful seller on eBay. It somehow sounds a little wired that we talk about mechanism design (say, whether eBay's ecological system is better than Taobao's) without personal experience.

To step in, I should try - and there was a precious opportunity for me to do so! After the China-R conference in Beijing, two professors from Australia (Graham Williams and John Maindonald) asked if they could buy additional packs of the playing cards somewhere so they could share with their colleagues and friends. Then why not on eBay?

Then I typed "ebay.com" in my browser... log in...sell...The photos were prepared several months before... upload... done!

However, when I was trying to copy the link...it was so long!

http://www.ebay.com/itm/R-Language-Playing-Cards-Postcard-Suit-Best-Gift-Statisticians-/321134725623

Then I noticed the lovely "share to twitter" button on the left ^O^ Let me just use this one!

A simple click leads to a new tweet... of course I need to at some useR... Yihui should be the best choice 😛

Not sure what has happened during the night... when I wake up next morning, they are almost sold out (I listed 10!). Well... then the painful shipping process comes. Thanks to the fantastic e-packet tool(http://shippingtool.ebay.cn), it was pretty convenient to complete shipping online. OK, the postman will take care of them. Goodbye, my cards...

The special benefit is that now I realize how powerful the social network could be. Without spreading information through twitter, it would be much slower if we manually copy and paste the URL in emails. Social network sites control it just in the right way - "word of month" helps customer selects goods based on their reliable information source. Some comments:

Karthik Ram ‏@_inundata 30 May

Totally bizarre #rstats playing cards for sale on @ebay. http://bit.ly/18BmwTg 

Geoff J ‏@geoffjentry 30 May

@_inundata I once bought a "used wife" on @ebay yet somehow this is odder.

Ok...is it that wired?

BTW, the integration of eBay site and twitter is pretty good. Once the link is attached the listing image also appears. See below.