Web apps have exploded in the last year or two, going from simple document creation to apps that can do everything from edit text, audio, photo and video content. Some have even pushed the envelope into realms unimagined.
Web apps run in the browser, using Java and/or Flash (with HTML5 coming soon). They often have connections to online storage and built-in sharing ability. Generally, all you need is a modern browser with recent plug-ins.
Google is one of the leaders in this area, providing all sorts of capability through a collection known as Google Apps. (This can be confusing: there are apps collected under this moniker, like Google Docs and Calendar, and then there is a service called Google Apps which allows website owners to use that first collection instead of having to roll their own solution on their servers. I keep them straight by attaching “standard or premium” to the latter, since it has two levels of service, and that helps keep them straight.) Google Apps are available to anyone with a Google account or (to a limited extent) to Google Apps Standard or Premium clients. (Update: Google has made almost all Google Apps available to Google Apps Standard or Premium clients and promises to get the rest up and running soon.)
There are others, from the similarly multifaceted Zoho and Aviary to the focused Piknik and Photoshop.com.
