TabAway - Mozilla add-on that allows you to clase any tab with double-clicking.
Version: 2TabAway allows you to close your current tab by double-clicking the tab you're going to. Be faster and more focused.
Operating System: Mac OS X
Note This version doesn't miss clicks, so if the browser stalls and you click nervously again, when it wakes up the tabs might move and you may close what you didn't want to close.