Any Plugins That Do This? Managing Downloads Transfer Speeds

I’m basically looking for a plugin that not only manages downloads in its own page + categories (I guess a download directory… I know I’ve seen one, but can’t seem to find it here anymore).

And then I need something to control download transfer speed rates. I’m not sure is a plugin would be able to control this, but basically what I want it to be able to do is give different download rates for non-registered users, a faster rate for registered users, then an unthrottled speed for subscribed (paying) users.

I guess this’d have to be a custom job.

Am I right!?

Thanks for any help ahead of time.