Yes, I had an account with them... unfortunately they only offer Chinese language interface. They created Alipay as payment processor for their auction site TaoBao, it's something like Ebay-PayPal.
Alipay is the payment processor created by Taobao.com, a very popular chinese auctions portal.
The story is something similar to Ebay.com and PayPal.
Go there and create an account if you want, but it's better if you know a little of chinese.
Never heard about it till now. I guess from the name, it could be related to the most popular online shopping site alibaba. I guess alipay could only used only on their site? can someone clarify this?