Update: Chrome now supports Greasemonkey userscripts natively now. Just click the link for the userscript (downloaded from userscripts.org or any other site) and Chrome will load it and display it in your extensions window.
One of the biggest complaints of Google Chrome users is that the amount of customization one can do is minimal. Hackers have already found ways to install custom themes, create a portable Google Chrome and block ads.
One of the most popular Firefox extensions is Greasemonkey – which most Chrome users envy. Though there have been some clumsy workarounds of installing Greasemonkey in Chrome with bookmarklets, there haven’t been any proper solutions.
Meet Greasemetal. Greasemetal is a small, 1.2 MB application to hook up userscripts (Greasemonkey scripts) to Chrome. Greasemetal does not have any user interface, so scripts that have to be managed (for example, if you need to add any details to get the script to function properly), Greasemetal will not work.
First, download Greasemetal and install it. After installation, launch Greasemetal from start menu. Greasemetal will in turn start up Google Chrome.
Greasemetal source code is available for all to see, so hopefully other smart developers will look into the code and develop other extensions (hint, hint!). Until Chrome gets extension API officially, of course (which will be soon).
Related: Google Chrome Backup backs up and restores Chrome and Chromium profiles