A leg-locking oak "capture chair" is among the headline lots at Christie's Out of the Ordinary sale in London on September 3.
The lot, estimated at £25,000-35,000 ($42,438-59,414), features metal bars hidden within the structure that shoot out and trap the sitter.
It carries the somewhat ironic inscription "Welcome to My Friends" below the seat and can be escaped by pressing a switch at the back.
Also featured is a set of German Maximilian armour with a detailed face design on the helmet.
It's named for Maximilian I (1459-1519), Holy Roman emperor during the 16th century, and features elaborate fluting and etching designed to mimic the fashions of the period.
The reproduction offered in the sale was built during the Victorian era and is expected to make around £25,000-35,000 ($42,438-59,414).
Three Danish Glass Models of Jellyfish in Tubes, an artwork by Steffen Dam, is valued at £8,000-10,000 ($13,573-16,966).
Dam produces detailed models of marine life in jars and is regarded as one of the world's best glassmakers.
Last year's sale featured a diverse range of items, including a Triceratops skull and a set of Francis Bacon's paintbrushes.
You can click here to check out our selection of weird and wonderful collectibles.
Why not sign up today for our free newsletter?