Did you know that you can preview You Tube videos, Flickr, Picasa, and Yelp images in your gmail, when you receive a link in the body of an email? Well you can and it's easy to do! Just follow the following steps:

Go to Settings

In Settings click on Labs

Scroll down until you see the You Tube, Picasa, etc. options and click on Enable then 'Save Changes' at the bottom of the page

You should now see this green icon next to the Settings tab which indicates you have Labs enabled.

Now just open up the email with the link and preview away!