Use multiple Chrome profiles at the same time

To create a profile

Create a folder on your computer, say C:\chrome-dev-profile.This folder will hold the data for the new profile.
Make a copy of the Google Chrome shortcut on your desktop. (Right-click, then Copy.) Name the new shortcut something like Chrome Development.
Right-click the Chrome Development shortcut, choose Properties, and paste --user-data-dir=C:\chrome-dev-profile at the end of the Target field. The result might look like this:

"C:\Documents and Settings\me\Local Settings\Application Data\Google\Chrome\Application\chrome.exe" --user-data-dir=c:\chrome-dev-profile
Start Google Chrome by double-clicking the Chrome Development shortcut. This creates the profile data.