Now available from Preware! Look under the Browser category for Add Search Suggestions to Web URL Bar.
Here's a patch that I was working on for the past week. Simply put, it adds search suggestion results to the popup list that appears when you start typing something into the URL bar. Search results are appended to the bottom of the list, to a maximum of 32 total entries (browser default, not set by me). So if you've got a lot of hits for history and bookmark results, you won't see any search suggestions.
The suggestions are from your default search engine, set from Just Type and Web preferences (they're actually control the same option). Your Just Type search provider must provide a search suggestion URL for this to work. To check, go to Card View and hit Just Type, and start typing anything. When the results list appear, look beside the entry for your default search engine and see if there's a Suggest button. I don't think TouchPads have the search suggestion URLs anymore, so I rounded up Google and Wikipedia from Firefox. Please find a package that adds those suggestion URLs to Just Type here. It's a modified version of bi0tech's Google URL fix.
The suggestion poll time is set to 3 seconds, so it doesn't delay your history list showing up. In the future I may have the history list return immediately and load search results when they come.
Bug that you should never encounter: Search suggestions that don't match what you have typed. I fixed that by not adding results if the query doesn't match what's currently in the URL bar.
Bug that you may encounter: Scrolling down in the list and then typing in some new words may cause the popup to become unscrollable because there are less entries. I'm not sure how I can fix that. It might be the way VirtualRepeater works.