2. Wiki: Socialtext
Where it comes from: Since its founding in 2002, Socialtext has been in the business of bringing social software such as wikis to the enterprise. They don't make their money off ads, so the free version of Socialtext (up to 5 users) is more or less a way for them to show businesses it is worth their time and money to sign up for their enterprise version that supports more users and contains more features.
Getting started: Go to Socialtext's customer login page and click on "get your own free Socialtext wiki."
Ups: Wikis do very well at providing users with context for the content their reading and consuming, and Socialtext is very good in this regard. You can embed content from within the confines of a social software environment (such as another wiki page or blog) as well as areas of the public Web. As an example, you can embed Google search results and RSS feeds rather easily by clicking on the "insert" drop down menu. It has good mobile access and the ability to take a wiki offline. Ability to tag content for easy discovery later on. If you're enamored enough by Socialtext's wiki, and want to expand your social software usage, the company also now gives you platform in which to create a blog.
Downs: While the editing tool allows for someone to post with no coding experience (just like Google Sites), it's not as pretty looking as the Google Sites text editor and has fewer options around font types. It's only free for only up to five users.
3. Wiki: Wikispaces
Where it comes from: Wikispaces is a three-year-old San Francisco start-up that focuses on hosting wikis for everything from businesses to schools.
Getting started: Pretty easy. Go to wikispaces.com and a light green sign up box can be found in the right corner.
Ups: The free version of Wikispaces doesn't have any limit for the amount of users and offers 2 GB of storage. The WYSIWYG (What You See is What You Get) editor is cool in that you can move it around the page to where you like it best. One elegant feature allows users to embed widgets (such as a YouTube video) very easily and have it appear nicely on the page. A "history" tab allows you not only to list previous versions but to compare them as well.
Downs: No mobile access and they've got to pay the bills, so they might serve up some ads along side the application.