Userscripts.org

Adds a "Get Link" button which allows you to access and copy the the persistent URL of an email conversation thread in Gmail.

Remove/hide all unnecessary elements on Google Sign-In pages

Removes the annoying ads at the bottom of your Gmail message threads

Removes the "No new mail" notice from your empty Gmail inbox

This script improves Google Mail's new look to be more neat and save space with additional keyboard shortcuts (set display density to compact) [all ads & feedback removed]

Everybody is disappointed by gmail's new UI. This small piece of script tries to colorize the new UI to make it a little bit easier to use.

Removes all ads in Gmail, including Web Clips at the top of Inbox. Updated for the most recent Gmail design.

Hides the right hand sidebar in the message view in Gmail for an extra-wide widescreen view.

Add extra emojii to your Gmail chat! Compatible with Firefox, Chrome & Opera =)

Adblock for GMail

Shows the number of unread Gmail messages in the FavIcon in your Firefox tab.

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)

Dim Ads for Google Mail

See from your inbox what kind of attachment an email has

Use Ctrl+Shift in Firefox to switch between RTL and LTR modes in gmail

Adds strikethrough button to Gmail rich text editor

Makes "mailto" links open in your favorite web-based email account, instead of a pop-3 client (like Outlook, Eudora, Thunderbird, etc.) Supports Gmail, Yahoo Mail, and Google Apps Mail. [UPDATED Dec 2011]

Removes the people/advertisement sidebar when using the Preview Pane labs feature

Audio & Favicon alerts for New Mails or Chat msgs. (Cross-browser compatible!)

Working combo-mod of Wooley's Gmail Favicon Alerts 3 & Santosa's Gmail Favicon Alerts.txt because neither alone worked in Chrome for me.

Disable Gmail's "Consider including" email recipient recommendation functionality and other annoyances.

Gmail + LaTeX = GmailTeX

Shows google reader unread count in Gmail nav bar.

Smaller text (0.85) and labels to the left in message list.

GM script that hides Producteev snippet on Gmail

Google page-enhancer turns all Google service pages BLACK: an inverted color scheme for reduced eye fatigue. It improves usability, page layout, widens search results and can remove clutter & improve security.

Got stupid administrators that force Insightly down your throat? This script will hide Insightly blocks below emails.

UI tweaks to Gmail's new "Preview" theme

Format "Deus lo Vult!" blog's messages in Gmail conversations.