I have posted about Installing Cisco Packet Tracer on Ubuntu 13.04 and prior versions. But this method is not working on Ubuntu 13.10 because of a repository issue, I think. Medywan posted a link. I followed the link and found a new way. But it was not in English, so I translated it.
Thanks to the author who posted it first: http://www.be-root.com/2013/11/19/installation-de-cisco-packettracer-6-sur-ubuntu-13-10-64bits/ Credit should go to him!

Run those commands in the terminal first.

sudo dpkg --add-architecture i386

sudo apt-get install libnss3-1d:i386 libqt4-qt3support:i386 libssl1.0.0:i386 libqtwebkit4:i386 libqt4-scripttools:i386

After that, install using the bin file. “Cisco Packet Tracer 6.0.1 for Linux – Ubuntu installation (no tutorials).bin” would be the filename. This name is too long for me. Then I renamed it to “ciscopt.bin“. chmod +x ciscopt.bin

./ciscopt.bin

Thanks again to Medywan and the author http://www.be-root.com/ site!