One of my biggest problem with chrome was the inability to use multiple profiles. Testing the site with users with different privileges, logging in/out all the time is very time-consuming.

Also, keeping private life separated from office was an issue — different gmail, different pivotal tracker login, different github account, different tabs, different everything. Logging in and out all the time is not an option. Using Firefox for one and Chrome for the other is passable, but not perfect. First, what if you need more than two sets of logins? I am actively using four profiles. Chrome, Firefox, Iron, Safari? Give me a break.

Finally, Chrome addressed the issue, and multiple profiles are in the dev builds. It works very well, it even remembers the tabs opened for each profile. Here is how you can activate it:

1. Download developer version from http://www.google.com/chrome/intl/en/eula_dev.html
2. Install it, then type in chrome://flags into the address bar. On the page, search for multiple profiles. Enable it.
   
3. Restart your browser
4. type in chrome://settings/personal into the address bar. Now you will see a ‘Users’ section. Click Add new User. It immediately opens a new browser window (not a tab) with the new user selected. Now you can see the the profile marker on the top right corner of the window. Close this window, and you will see that in the preferences screen now you have two users: a default user and ‘User 1′. You can now edit the profile names and customize their icons.
   
5. Restart Chrome again. Now the profile marker will be visible on the main window as well, and you can switch users at ease. Every time you switch a user, a new window will be opened, and all tabs of that user will be restored from the last session.

@akomba