It is common truth that social web sites have dominated the web during the past few years. This results in the creation of vast amounts of information that is being produced by the corresponding user activities. Traditional information organization tools originating from the library domain are not applicable to the social web due to its overwhelmingly dynamic nature. Along these lines, hashtags have become an information organization tool of growing popularity among social web sites. In this paper, it is argued that digital libraries may exploit information deriving from hashtags bringing this way two fundamentally different worlds closer to each other. Thus, a methodology is proposed, where popular hashtags are expanded through semantic web technologies and are ultimately matched against the subject index of a digital library. Successful matches are promoted to the homepage of the digital library to suggest trending resources to the end-users.