This network is described in Patterns and Dynamics of Users' Behaviour and Interaction: Network Analysis of an Online Community and used in a number of articles including Prominence and control: The weighted rich-club effect and Clustering in weighted networks. Although this dataset contains many nodal attributes (e.g., gender, age, and course attended), these are not made available as it would be possible to reverse engineer the anonymisation procedure of users. Self-loops in the original longitudinal edgelist signal the time that users registered on the site, these have been converted into vertex onset times and removed.
As this dataset excludes isolated vertices, for analyses involving degree distributions it may be desirable to add them back in. There were a total of 2595 users that logged in at least once -- and 2995 users that filled in the registration form (might not have validated their email etc).
This dataset is also included in the CRAN package tnet
.