Although the advent of the Internet has increased the amount of information about primary sources online, the intellectual accessibility of archival materials and researchers' ability to effectively reuse digital archival materials and surrogates is not known. Many of the online representations of archival information, e.g., finding aids, mirror their paper counterparts both in look and in functionality and do not take advantage of the electronic environment. This paper describes the design, implementation and launch of a new type of archival access system, the Polar Bear Expedition Digital Collections (http://polarbears.si.umich.edu) which provides traditional searching, browsing, and interlinking as well as social navigation features such as collaborative filtering, commenting, and awareness of other registered visitors.