Online guide to Google Wave

http://completewaveguide.com/

Unix cheat sheets

http://www.techieblogger.com/2009/10/linux-unix-ubuntu-solaris-cheat-sheets.html

jQuery cheatsheet

http://woorkup.com/2009/09/26/jquery-1-3-visual-cheat-sheet/

Free Linux tips ebook

http://www.thegeekstuff.com/2009/02/linux-101-hacks-download-free-ebook/#toc

Free IT posters

http://posters.msug.vn.ua/default.aspx

SQL injection cheatsheet

http://ferruh.mavituna.com/sql-injection-cheatsheet-oku/

Free Firefox tips ebook

http://www.firefoxfacts.com/ebook/FirefoxFacts.zip

CSS3 cheatsheet

http://www.smashingmagazine.com/2009/07/13/css-3-cheat-sheet-pdf/

HTML5 cheatsheet

http://www.smashingmagazine.com/2009/07/06/html-5-cheat-sheet-pdf/

CSS cheatsheet wallpaper

http://thewpresser.com/css-cheat-sheet-wallpaper-in-helvetica/

RegExp resources

http://www.smashingmagazine.com/2009/06/01/essential-guide-to-regular-expressions-tools-tutorials-and-resources/

Free ebooks for Linux newbies

http://www.linuxhaxor.net/2009/05/10/10-free-linux-ebooks-for-beginners/

Ubuntu book excerpt

http://www.linuxjournal.com/content/excerpt-practical-guide-ubuntu-linux-versions-810-and-804-2nd-edition

Web design cheatsheets

http://delimitdesign.com/design/14-incredibly-useful-web-design-cheat-sheets/

Python cheatsheets

http://www.onlamp.com/python/excerpt/PythonPocketRef/

PostgreSQL 8.3 cheatsheet

http://www.postgresonline.com/journal/index.php?/archives/91-PostgreSQL-8.3-PSQL-Cheatsheet-Overview.html