Although Evernote syncs everything through the cloud and offers a fairly sophisticated Web-based platform, the application is actually centered on its local clients for Windows and OS X. It also is available in apps for several mobile platforms, including iPhones, iPads, Android devices, BlackBerry phones and the Palm Pre. Your information is synced across these platforms.

These local clients ensure that users have access to their data whether or not they're online -- something that is useful for those who depend on Wi-Fi for an Internet connection away from home or the office. For example, if I want to take notes at a meeting where I'm not sure I can get online, I bring up Evernote on my (I haven't joined the tablet forces yet) and type away, secure in the knowledge that as soon as I'm able to connect to the Internet again, Evernote will automatically sync the new note with the rest of the database.

Evernote is available in a free ad-supported version that allows users to add up to 60MB of additional data per month. (There's no cap on how much aggregate data you can store over time, just a limit on how much new information you can add each month.) A premium ad-free version ($5/month or $45/year) lets you add up to 1GB of new data per month; it also synchronizes any files you attach to your notes, while the free version syncs only images, audio and PDF files in addition to your notes. Premium users enjoy a variety of other advantages as well, such as improved support and access to note history.