UI Metaphor for sorting large lists

As part of a web app, I have a queue of items that need to be sorted in an arbitrary order.

If there are a few items (say less than 20) I can just present it as a list and let the user drag and drop rows around to set the sort order.

But if I have a lot of items (say, more than 100) how can it be done? Are there any existing metaphors for sorting a large list like this?

From stackoverflow

• I've had a similar thing in a previous application i worked on, and i found the best solution was to organise things hierarchically, and let the users sort things at a different level at a time.