Mayonnaise round 2; the rematch
So, apparently our whisks have sublimated into the luminiferous ether. At a guess the refusal to hand wash them led to corrosion and subsequent disposal. Since a already had the egg yolk in the bowl and the oil measured out before starting... I went even lower tech and grabbed a fork.
A grueling but tedious battle ensued. But I have turned one egg yolk, some dijon, a cup of oil, some vinegar, and salt into something that looks like mayonnaise. Victory!