It’s not quite the same as the results-as-you-type-every-letter Google Instant, but Chrome’s Dev channel and Canary builds offer a switch that turns on a kind of instant search for Chrome’s Omnibar, which you may find really helpful or kind of distracting.
If you’re running the Dev version of Chrome (you can switch over here) or the Windows-only Canary Build, you can add the following switch to a Google Chrome shortcut (explained in this guide) to activate the “match preview” feature:
As the Google Operating System blog points out, it’s not exactly like Google Instant. The results show up for exactly what you’ve typed in, without an educated guess as to the word you’re heading toward. The Google search shows up as an inelegant page break-in a bit below the content of the page you’re looking at, and if you use your arrow keys to drop down to one of Chrome’s suggestions, you’ll see a preview of that page load into the Google search space:
You might find this kind of instant search result preview helpful or find it slows down your Omnibar typing game. Either way, it’s easy to turn on and off with the command-line switch and will likely improve in future versions.
Instant Search in Google Chrome [Google Operating System]