I love starting out research in a state and finding that their birth or death certificates for a large range of years are available online! Or next to that, finding that they have those vital records indexed, and searchable, even if the actual document will require a fee. Arizona tops my list with searchable birth and deaths ranging from 1844 to 1958, and the results including a PDF of the actual certificates. Other states however are quite "stingy" with their information it seems. What states do you like or dislike?