IE7 Pro adds a lot of showmanship to the Internet Explorer browser. The freeware add-on has some smart solutions for tabbing, including default settings to open URLs in new tabs and let double-clicking close a tab down.
Here's another pleasant surprise: "Dragging" and "dropping" an in-text link into white space opens the link in a new tab without any mouse work. IE7Pro also borrows from several software concepts to help raise IE7's appeal, including Firefox's, to save and fill forms, and insert user scripts a la Greasemonkey. The MiniDM download manager adds a long-missing tool to IE's options, and the prefetching options makes IE much lighter on its feet.
The list of added features is long, but they're all accessible from a status bar icon that the program installs for you. Right-click on it to get access to mouse gestures, customizable hot keys, and more. Highly recommended.