Cacher is the code snippet organizer for pro developers

Menu Vertical
http://jsfiddle.net/neves/wtZVY/

Menu Horizontal + float
http://jsfiddle.net/neves/ypnLp/

Menu Horizontal Inline
http://jsfiddle.net/neves/cRPQ2/

tags HTML5
http://jsfiddle.net/neves/89GPD/3/

Exercicios:
http://images.patterntap.com/1/9/1930642019481be68c3813d.png
http://images.patterntap.com/1/5/1574561044481be103409a8.png
http://images.patterntap.com/1/8/1834693945481be5bdac0ca.png

Sites:
http://cssdesk.com
http://jsfiddle.net
http://html5doctor.com/
http://border-radius.com/

Firefox Extensions:
http://getfirebug.com/
https://addons.mozilla.org/pt-br/firefox/addon/web-developer/
https://addons.mozilla.org/pt-br/firefox/addon/colorzilla/