scroll to top of page-sticky menu that floats

I have seen a small link that floats on top of everything bottom right corner and comes along as you scroll. To go to top of page, one can click on that.

Is it a javascript?

Can somebody point me to such a script?

I wish to put that only on certain pages of WP201 blog. Can it be included along with page’s content?

please help.

Thanks,

drb

EDIT:
Just found it:
http://www.dynamicdrive.com/dynamicindex5/jumptop.htm

Hope it is useful for newbies like me. Hence I posting the solution.

EDIT:
But not sure how to get [top]link closer towards center. It is way bottom left and hard to see. My WP blog is all centered.

Any ideas?
Thanks,