Userscripts.org

Makes Google 3 times faster, doesn't sound like a lot but it makes a big difference.

Adds a "Mark Read" or "Mark Unread" button to Gmail pages (active only when mail items are selected). This version fixes all wrapping issues, and allows to work even on GMail for Domains.

Greasemonkey script for Firefox to change the appearance of GMail

GMAIL: Draws the labels on top of the active window so that you dont have to scroll down

Hide certain Gmail labels

Adds Quick Link Navigation to GMAIL

Automatically click's "Alway's Show Images" in GMail

Auto sign in for Google, not just iGoogle or Gmail!

Adds a compose link to gmail section of Google IG homepage

Several customizable options. Special support for Userscripts.org (new interface, fix for pre tags, and allows you to hide the install warning box and footer) Changes text fields, buttons, links, selects, and text areas.

force GMail to use secure connection

remove text adds from google web mail

A template for creating new user scripts from

Disable Gmail's "Consider including" email recipient recommendation functionality (aka "Add: [Some person]"

Add icons to Gmail labels

Modified Hide Gmail Right Side Ads, also removes the 'about these links' bit.

Append the function to apply the mail template, when writing a mail.

Adds web-based annotations to Gmail.

Only show unread labels in Gmail

Automatically add email addresses to the Cc or Bcc field in gmail

This enhanced the famous Folders4Gmail script with something like the Label To Top script.

This script replaces the display name of the sender and recipient from the sender's expression with your registered expression in your address book.(can work on google chrome and firefox-greasmonky)

Makes mailto links open cleanly in a Popup GMail window - Google Apps or Regular GMail

This maximizes the vertical real estate in GMail by collapsing the links on the left to an image box, and moving the search to left side (This is a modified version of Pavel Gutin's original Gmail Compactor).

Adds Google Reader subscriptions to Gmail

Adds Google Docs to Gmail

Moves labels with unread conversations to top of "Labels" list in GMail.

Adds a fixed font size toggle button.

Fixed-font message bodies toggle for GMail (new UI/API version)

Adds a special right click on menu to Gmail. Default right click menu remains visible