Wikis are a free simple website creation tool that you can use in a variety of ways
(there are other like WIX or Square Space)

Sample Ideas:

Classroom Website
5th Grade Classroom

Library Website
Centennial Library Website

Course Website
My MS Tech Arts Website

PD
My staff PD on creating their own wiki

Elementary Digital Student Gallery
MS Digital Student Gallery
This is a example of a digital showcase

Teaching Platform
Sample Intro Lesson for 8th AP History Unit - using tech to get kids thinking up front


Resources explicitly for Wikis:

Getting Tricky with Wikis great source of editing techniques

Advanced Wikispaces by Dr. Candy McGregor - TIE presentation with tutorials - awesome !

Cool Tools for Schools Wiki - unlimited resources