There is probably at least one field of knowledge in which you are an expert. Maybe it's an area of technology, or perhaps you're the go-to person when it comes to hiking in your local area, creating amazing desserts, or grooming pets. Whatever your forte may be, you can use Wikispaces (free for personal use; paid plans start at $5 per month) to share your knowledge in the world and even create a community of enthusiasts.

Not being able to make your free wiki private is not a major issue: These days, websites need to work to be discovered. If you're just setting up your wiki and slowly adding content, you can keep quiet about it until you're ready to share it with the world. Chances are almost nobody will stumble upon your exact wiki URL--which takes the format of "yourchosenname.wikispaces.com"--by mistake. Wikispaces also lets you change the URL for your free wiki at any time, as long as it's under the Wikispaces domain. So you could use a random "staging URL" and change to your domain prefix of choice once you're ready to share.

The Wikispaces editor is visual, so anyone who has used a word processor before will feel right at home--wiki syntax isn't required (although it is allowed). It also has an interesting feature called Widgets that lets you embed rich content from all over the web, so putting a YouTube video or a Flickr slideshow into your page takes just seconds.

Note: The Download button takes you to the vendor's site, where you can register to use a this online software. Prices vary by user type (business, education, personal).

--Erez Zukerman