UPDATE: This method no longer works in new Google Chrome versions. Check following topic to get Chrome themes:
Although Google's new web browser "Chrome" doesn't provide any way to change its theme but you can install custom themes using this tutorial. Even you can create your own themes.
All Chrome UI files are stored in a single file "default.dll". So you just need to edit this file to create your own theme and there are already some ready-made themes available to download.
So here is a step-by-step tutorial to install and create custom themes in Google Chrome:
1. First you'll need to find this "default.dll" file to replace or edit it. Type following string in RUN dialog box and press Enter:
local settings\Application Data\Google\Chrome\Application
NOTE: Windows Vista users can also type "appdata" in RUN or Start Menu Search box and press enter, then navigate to "local\Google\Chrome\Application".
2. It'll open a folder containing Chrome files.
3. Now when you are in "Application" folder using 1st step, you'll see a folder having some random characters in its name. Open this folder and go to "Themes" folder. That's it, you'll find the "default.dll" file in this folder.
4. First take a backup of this file before replacing or editing it, so that you can restore it if you want to get the default look back.
5. Now open this file in "Resource Tuner" and expand "BINDATA" folder.
6. Under this folder, you can replace the existing PNG files with your custom PNG files. Create your own PNG image with same dimensions using Photoshop, Gimp, etc. and then replace existing PNG in the "default.dll" file with your one.
To replace the existing PNG file with your custom one, select the PNG file in Resource Tuner and then press "Ctrl+Shift+E", it'll open another window asking for your own resource file. Press "Ctrl+O" and browse to your own PNG file, select it and click on "Open" button and then click on "OK" button.
When you have replaced all desired resources, save the file and you have done.
Since Chrome supports PNG files, there are lots of possibilities for theme creators to put transparency in their themes.
7. You can also download some 3rd party ready-made themes. Just download them and you'll get the custom "default.dll" file. Replace the default file with this new one as mentioned in above tutorial.