ColorfulSidebar offers a simple but pleasing visual modification for OS X 10.7's Finder.
OS X 10.7 brought greyscale icons to the Mac OS X Finder window sidebar, but if you'd rather have some color back in your desktop window sidebars, you can get this done easily through a third party plugin.
If you've been following some of our other Lion tips, you may already have SIMBL installed, otherwise it's a small download.
If you ever want to get the grey icons back, you just need to remove the ColorfulSidebar.bundle file from the SIMBL plugins folder and then relaunch the Finder again.
On a somewhat related note, you can also bring back the personal folders in your OS X Lion Finder window sidebars. Those icons will gain color again too.