Internet Tips: Gmail to the Max--Helpful Tips, Tricks, and Hacks
Preview Your Gmail Conversations in a Bubble
Inspired by Google Maps' bubbles, current Google employee and occasional shareware author Mihai Parparita wrote a Greasemonkey script that pops up a preview of a Gmail conversation thread when you right-click it. First, install the Greasemonkey user scripting extension for Firefox. Next, visit Parparita's blog, click one of the links there that display the Conversation Preview Bubbles script, and select Install in the Greasemonkey toolbar. You can now read the threads in the Google window.