BibDesk is a graphical BibTeX-bibliography manager for Mac OS X. BibDesk is designed to help organize and use bibliographic databases in BibTeX .bib format. In addition to manual typing, BibDesk lets you drag & drop or cut & paste .bib files into the bibliographic database and automatically opens files downloaded from PubMed. BibDesk also keeps track of electronic copies of literature on your computer and allows for searching your database through several keys.
BibDesk integrates well with TeX for creating citations and bibliographies. This integration includes a Citation search completion service, and drag & drop (cut & paste) support for adding citations to TeX files.
Other great features includes PDF archive management, annotation, HTML exportation.