Cooliris Previews is a must have browser addon for power surfers. It boosts your efficiency by adding a Cooliris icon near every link, hovering over the link will open the content of underlying page in a new window.
The preview isn’t just a screenshot, you can actually browse the page, visit links or even watch videos through the preview window, as if it was a tab. The preview window automatically closes when you move the mouse away. The preview window also contains some buttons which can share the link with your friends, open the page in new tab or lock the preview window (so that it doesn’t close when you move the mouse away). This video will give you a better idea:
Cooliris comes extremely handy while searching the web; you can see the results, before actually visit the page. Initially developed as a Firefox Extension, Cooliris Previews is now available for Internet Explorer and Safari as well.

wrote, on March 14th, 2007
Not really a must have, I installed it sometime ago and I don’t like it. Kinda annoying sometimes.
wrote, on March 14th, 2007
well far much better than the annoying snap preview….
wrote, on March 14th, 2007
I had been using it from last 4 days.Its really cool.Helps me specially when i have to move around through wp menus.If people start browsing through this our page views will get low ,…
wrote, on March 14th, 2007
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wrote, on March 14th, 2007
Yeah its something like snap but I dont click a page unless I am going to read something there, So I dont like preview links. But some do like it
wrote, on March 15th, 2007
Mr.Byte: Same with all of us, but the problem is how will we know that the link contains something we need ?
wrote, on March 15th, 2007
I think this plugin is far worse than snap, and I hate snap. Definitely not a plugin I will be getting.
wrote, on March 16th, 2007
Me neither. I see this one as a kind of annoyance.
Thilak, you have a a point in your question. We really “burn” time clicking into websites which are totally useless for us. Maybe some textual info on the site is what we need.