Flappers 2 Rappers
http://www.webster.com/lighter/flap/flaphome.htm
Tom Dalzell's intro to his book, delineating the twentieth century youth slang.

The Phrase Finder
http://phrases.shu.ac.uk/
Find the origin of "The Smallest Room in the House" among many, many others.

Similes: Steal some of these similes for your next speech
http://www.tallrite.com/LightRelief/similes.htm
Some silly similies. Ex. "She had a deep, throaty, genuine laugh, like that sound a dog makes just before it throws up."

Word Puzzles

Complico Paper Folding Puzzle
http://www.uniqueprojects.com/projects/complico/complico.htm
Scroll past the Google Ads to see steps on how to create a paper word puzzle (there's 9 on 'em with solutions)