Etymological Wordnet looks promising, even if I don’t understand quite how it works; their website says:
The Etymological Wordnet project provides information about how words in different languages are etymologically related. The information is for the most part mined from Wiktionary. The semi-structured data is turned into a machine-readable etymological database that also incorporates some additional manually added etymological relationships.
A very basic interface to the data is provided at lexvo.com. A more advanced browsing interface will be available later.
But when I click on the lexvo.com link, I get “Unable to connect: Firefox can’t establish a connection to the server at www.lexvo.com.” At any rate, I thought I’d toss it out there for adventurous lovers of etymology.
And speaking of etymology: “Two new antedatings of hot dog!” Fred Shapiro has taken it back to November 14, 1886, and the source (from the Nashville Tennessean) is quite striking: “‘Hot stuff,’ ‘hot pup,’ ‘hot dog,’ sings out the fiend who carries in one hand a tin cooking arrangement, and on the other arm a basket. He is the wiener wurst fiend. It is his cries that greet you as you enter the theater and regreet you as you come out. He is the creature whose rolls make the night hideous, and whose wares make dreams that poison sleep…”