I have read from Richard Bejtlich’s Twitter  and from the Argus’ Mailing list about the packet repository maintained by the University of Twente.

A quote from the wiki page,

From this location you can download anonymized packet headers (tcpdump/libcap), Netflow version 5 data and a Labeled Dataset for Intrusion Detection. Data is taken from various locations in the Netherlands. More information on the data collection and anonymization procedures can be found here.