Kirby vacuums. I got one for free from a neighbor and she included the invoice by mistake. $2200 for a vacuum that smells like burning and can't lift pet hair. Brush is working, bag is new, carpet is being lifted from the pad. But man, this thing fails at pet hair.
There was a brand that worked by filling the tank with water and applying a vacuum to use the water as a filter. They weren’t amazing but they cost like $2k in 2001 money. My ex had one that her father had bought and I finally convinced her to get rid of it once it started shocking her.