Record Search at FamilySearch.org
Though it's still a pilot, Record Search at FamilySearch.org is an amazing resource. If you know that you're looking geographically, you can narrow by area by clicking on the map. Or, if you want to work very broadly, just use the search boxes at the top of the page. The majority of the information is index entries only, but there is a number of resources where an index doesn't yet exist, but the images are included for your use.