Is there a website or service that shows you your websites pagerank throughout time? I'm pretty sure I had pagerank 2 sometime last year but since I didn't give it any attention, I am not sure if I remember correctly... stupid, I know Today my pagerank is 0, and Im not sure if I got some sort of penalty from Google or if everything is as it should be...
Not that I know of, no. Developing such a system would be a HUGE venture (think web archives, google's cache) simply because the page that would store the PR history would need to have crawled your page at least once after each PR update and record the data as Google themselves don't publish historical PR data. As for your site - leaving it 'as is', not updating it and not taking care in building your links is a very easy way to lose pagerank. Your site is not penalized (otherwise your PR would be N/A, not 0) but it has simply gone through a drop.
i am eager to know about such a type of website which is recording google page rank history. can any one suggest.
I think there is no such things, but it is commen that you site drop from pr2 to pr0 if you dont pay attention to it.