Yes, i am talking about that site which is now a blog site. After feeling a great curiosity, i talked with the creator of that site and that person told me that this was the portfolio website of a famous company of USA "acmepanel". For some reason they leaved .biz
and jumped to .com
when this site has ranked with pr7 though the company didn't applied any SEO tricks. Probably at that time, google PR rule was not that tough like today's and that's why it got high PR easily. I bought it then from an auction site after almost 1.5 years and in between this auction period, it lost it's PR and now it is pr4. Now i am maintaining this site and doing my SEO jobs with this.
Anyway, thanks to all of you for wonderful reply. stay well