I made a very simple AutoHotkey systray icon, designed to be similar with Window 7 systray operating system icons. Feel free to do anything you want with it. This is 16x16 size (with transparency).
Code for replacing the default icon (just change the path):
#SingleInstance, Force Ico :="C:\Tools\AutoHotkey\AutoHotkey-Windows7.ico" Menu, Tray, Icon, %Ico%, 1
Merry xmas!