Google Scholar enables you to search specifically for scholarly literature, including peer-reviewed papers, theses, books, preprints, abstracts and technical reports from all broad areas of research.
検索対象が論文の類に限定されるので，文献探しをする時に不要なものがマッチしにくくて便利そう．今のところ，日本語での検索は駄目みたい…