http://www.r- project.org/ : Free software environment for statistical computing and graphics, different kinds of analyses can be done, can use as a calculator
http://www.mendeley.com/ : Academic software for bibliography creation and research paper management
http://www.zotero.org/ : A free, easy-to-use Firefox extension to help you collect, manage, and cite
http://www.refworks.com/ : Online bibliographic management program (RefWorks) that allows users to create a personal database of references and generate bibliographies in a variety of formats
http://www.biblioscape.com/biblioexpress.htm : Free software (BiblioExpress) to collect reference data, and generate formatted references in popular styles such as APA, MLA, etc.
http://www.endnote.com/ : Acommercial reference management software package, used to manage bibliographies and references when writing essays and articles
http://www.ncbi.nlm.nih.gov/ : US government-funded national resource for molecular biology information. Access to many public databases and other references
http://workbench.sdsc.edu/ : A point and click interface for searching protein and nucleic acid sequence databases and for analyzing sequence data with different kinds of tools