To install use link below. After installation chrome restart is needed.

INSTALL

tested on:
  4.0.249.0, ubuntu 9.10

current version
0.4
known issues:
scrolling not works on blank tab and chrome://extensions/
changelog (0.2 -> 0.3):
fixed bug "sometimes tabs scrolls, while mouse button is not pressed".
fixed bug, that while tabs were changing, the sites were scrolling down/up.
removed autoupdate (lack of proper hosting for now...)
added scrolling while left alt is pressed.

future plans:
options page will be added with ability to change left button to middle or right button.
known bugs will be fixed

my extension on chrome.google.com/extensions
written by: kasztan (at gmail d0t com)
blog (in polish)

Please write a comment, if you find the extension useful.