Some ideas:
www.linesacross.com/2012/04/dog-and-cat-paper-gift-boxes.html
http://sassafras.typepad.com/files/boxtemplate.pdf
http://www.linesacross.com/2012/04/make-your-own-paper-gift-box.html
Today's project is: http://www.linesacross.com/2012/05/paper-pyramid-gift-boxes.html