Must be a very long hill on which Dan made 90kph.
Still, I've made a ton...
I made a ton once on quite a short piece of road, behind a specially prepared truck (big panel-side truck, open doors at the rear, a sheet of ply attached to them to within an inch of the road to give me a stable air envelope), and the small country road, just resurfaced, was cleared and blocked by the tractors of friendly farmers at both ends, and all dogs were under restraint; normally I go down there at about 55-60kph on my present Utopia Kranich. The record bike, incidentally, was a Royal Dutch Gazelle Toulouse vakansiefiets (basically a fully trimmed city commuter of a price range usually saved by the Dutch for high days and holidays) running on standard 38mm Marathon Plus tyres and with my normal 38x16 transmission chain into a Nexus Premium 8-speed. For special prep on the bike, I fitted new pads to the front disc brake and pumped some grease into the rear roller brake, and I also reset the handlebars real low out front and rotatated with the grips almost vertical by opening the lever of the Switch stem, a Gazelle premium range standard fitting, placing the handlebars in the position and rotation I wanted, and closing the lever. That put my back not just flat but with a slope forward for some aero advantage; nothing else: didn't even remove the rack or mudguards or chain case or stand. For protective clothing I wore a tracksuit and my usual Bell commuter helmet, a Metro. I let the truck go when the handler standing inside the truck sliced his hand at about 65mph just as we came to the top of the hill, and what seemed only seconds later, just as I started to enjoy myself on the downhill side, flashed past the first brake marker (a shouting pedal pal holding up a board) and started hauling her up again. That was my personal ton-up (truck-assisted) record. Not a big deal for most, I suppose, but I thought I'd better do it before a fall meant certain hip replacement...