SEO Tools World

http://www.it-exchange.ro/en/tools/keyword-popularity.seo-report
http://www.it-exchange.ro/en/tools/meta-tags-viewer.seo-report
http://www.it-exchange.ro/en/tools/site-seo-strength.seo-report
http://www.websitegrader.com/
http://www.google.com/friendconnect/
http://www.google.com/intl/en/press/annc/20080512_friend_connect.html
http://www.NicheWatch.com
http://www.googlerankings.com/ultimate_seo_tool.php
http://www.iwebtool.com/backlink_checker
http://tools.marketleap.com/publinkpop/

pinging sites:
www.weblogs.com
www.blogRolling.com
www.Technorati.com

http://validator.w3.org/
http://whois.domaintools.com/
http://www.webconfs.com

301 check visiblity tool
http://www.rexswain.com/cgi-bin/httpview.cgi

pick keywords
https://adwords.google.com/select/KeywordToolExternal

www.seochat.com

Link popularity
http://www.marketleap.com/publinkpop/default.htm

rank checker
http://tools.seobook.com/rank-checkers/seobook

To increase traffic in your site, along with the above refer the below websites also.
NetVibes.com, windows live, stumbleupon.com, newsvine.com, Reddit.com, Digg.com,
Del.icio.us.com, Fark.com, slashdot.com