The People's Dictionary is an online Swedish-English and English-Swedish dictionary. It is based on Lexin dictionaries published by the Swedish Language Council, but this one can be updated based on user contributions. An interesting feature of this dictionary is the sound files that accompany many of the entries.
The book "201 Swedish Verbs" serves as a reference text for how to conjugate 201 common Swedish verbs in all of their tenses as well as a guide to Swedish conjugation patterns and morphology. Verb conjugation is often an area of difficulty for many foreign language learners, but "201 Swedish Verbs" can help students of Swedish learn conjugation rules and patterns, and drill them over and over again.
Sweden's largest daily newspaper, "Dagens Nyheter" -- also known as DN -- is published in Stockholm and covers both Swedish and international news. The Swedish-language newspaper has an online version as well. For intermediate and advanced Swedish speakers, reading "Dagens Nyheter" is a great way to learn more about Swedish society and Swedish vocabulary at the same time.
Similar to Project Gutenberg, Project Runeberg is a website where you can download copyright-free editions of Nordic literature free of charge. Most of the available texts are in Swedish, but some are available in languages such as Danish and Norwegian. Using the site you can have a steady supply of classic Swedish literature to read, which is a good way to build up your Swedish reading comprehension and vocabulary.
Sweden's public broadcasting system, Sveriges Radio (Radio Sweden), has four national radio stations in Swedish. Their programming, which includes news, music, entertainment, comedy and sports, is broadcast in Sweden as well as on the Internet. Regularly listening to Radio Sweden's programming is a good way to build up Swedish listening comprehension.
ProZ is a website for translators and has language resources and community features as well as job postings. For Swedish translators (or Swedish translation students), there are community-generated Swedish language glossaries containing some of the trickier words to translate. Site members can also ask for advice or help on translation issues.