If you find yourself in this situation, you have a few options:
- Video screen share over Skype or Google+ (handy if you're already connected using one of these, but Skype charges for that now, and you probably weren't already using Google+)
- Take a screen shot and email or otherwise fileshare it to them (thus filling their inbox/Dropbox/etc with an image they probably don't want to keep)
- Save an image and post it on Facebook (but your other 814 friends probably don't care to see it)
Here is another- and, I posit- better way to share a simple image of your screen over the internet.