FlagTab

Mark/Flag tabs via an unlimited amount of customizable colors. Quickly group and bookmark tabs based on color. Persistently label/color tabs by url/regex. Other optional features: relative tabs, Highlight unread tabs, color Favicon, and auto-flag. Use FlagTab to color and organize your tabs better. Features:+ Unlimited Custom Colors+ Multiple Triggers (click, double-click, mousewheel, various key Combination`s)+ Color Favicon Instead of Tab Background+ Relative Tabs (like IE7)+ Mark Unread Tabs+ Session Recovery+ Compatible with Most Themes+ Group Tabs (automatically) by Color+ Bookmark Tabs Based on Color+ Persistently Mark Tabs That Match a Certain URL/Regex+ Hot Keys (Alt+Ctrl+[1-9] to color current tab)+ Auto-color New Tabs (experimental)+ Auto-Rotate New Tab Color (experimental)