Preview Gmail Conversations

Mihai Parparita from Google created a brilliant Greasemonkey script last year. The script lets you right-click on a Gmail conversation and get a preview in a bubble. This way, you can read your mails faster, especially if you only want to read some of them.

The new Yahoo Mail and Windows Live Mail have a reading pane where you can preview your messages, but that takes a lot of space. This solution has the advantage that it's available on demand.

I know this is far from being new, but I've always wanted this feature in Gmail.

Greasemonkey details:
You need to have Greasemonkey in Firefox or Trixie in IE
Then install the script