There are dozens of screen sharing utilities out there (including those built directly into most popular video conferencing apps), but if you simply want to share your screen with a person or group at a distance there are two options you might want to explore. Both of the following solutions require a standard plugin and neither has an audio channel, but they allow quick connections sans account setup or login.

Screenleap.com offers a dead simple tool to share your screen with one or more people. Simply visit the site, establish a session and then share the nine-digit code (or related URL) with your audience and you're off.

Quickscreenshare.com offers a similar tool, which can only be shared with one person, but has an expanded feature set, including remote control (so that the sharee can drive your desktop).

Either tool could be used in conjunction with a conference call or voice chat to demonstrate desktop software techniques, offer a presentation to a course group, or to assist a colleague. Because neither tool requires a login or special software (beyond the ubiquitous Java Runtime Environment), a link or session code can be posted or announced via the course website or over the phone, allowing audience(s) to instantly access the screenshare at an appointed time.