Google Chrome is available with plugins. You can download amongst lots of Chrome plugins available. Though presently there are very less numbers of plugins are available, but developers are working very hard to make interesting plugins. Here are the list of some useful plugins which can definitely enhance your internet browsing experience:
Google Chrome extension for checking IP (As a Bookmarklet)
Google Chrome Extensions for Gtalk (Thanks Honey Singh)
GOOGLE CHROME PLUGINS FOR SEO (Amazing Plugin Thanks Rob)
Google Chrome Dictionary (As a Bookmarklet)
Youtube Video Download (As a Bookmarklet)
Note It is advised that use minimum plugin according to your requirement as these plugins take kick ass memory to run for. Just have a look on this snapshot of Google chrome Task manager which clearly indicates the memory usage.