How long does it take to go from Berlin to Duisburg? Thanks!

How long does it take to go from Berlin to Duisburg?

By train? Long enough that you could consider flying to Cologne with Germanwings. Flying also might work out cheaper, depending how far you book in advance.

See
http://reiseauskunft.bahn.de/bin/query.exe/en
From Berlin
To Duisburg

Should be something around 7 hours with ICE, longer if you use Happy-Weekend-Ticket.

You can do it in just under 3 hours (or thereabouts) by train, but it's not the cheapest trip.
Like t_maia said, German Wings would be a cheaper option. But book as far in advance as possible. GW are one of the most expensive budget airlines in Europe, if booked late on.

By car/bus it would take you around 4,5-5 hours. If you don't mind getting a ride with other people you could always try
Mitfahrgelegenheit/it's apopular ride share system. Unfortunately the website is in German only, but probably the cheapest you can get (Duisburg/Berlin costs between 20 and 30 €).

[ Edit: Edited on 18-May-2009, at 10:32 by steff ]