Food.

That's honestly all my money goes towards these days.

And utilities.

A pack of condoms

It's a bit dull but having the $100 in your pocket in case of emergency is pretty useful.

Another hardrive to feed my storage addiction.

A multimeter

£100 is roughly the price point for mid-range bone conducting, outside-the-ear headphones. These rest against the bone next to the ear instead of inside the ear itself. You can get lower end options for more like £45

I cannot recommend these strongly enough!

1. Your ear canal is open to the air, not plugged up for hours
2. You can still hear your environment, great for biking/walking/running/not getting snuck up on

• induction stove: you can buy a stand-alone element that plugs into the wall for about that much, and they're faster and use less power than a conventional stove
• bidet: a low-end model, at least
• multitool: should be able to afford a pretty good one for that budget
• cajon: all right, maybe not "useful" per se, but man they're a lot of fun!

a gram cocain

An electronics repair kit, e.g. the ifixit toolkit.

Well there's a lot of useful things that 100 pounds can get you. Depending on what you consider incredibly useful, and what you do everyday. A quick list of the top of my head:

• good quality first aid kit
• old/new but shit smartphone
• pair of decent working boots
• shit ton of used clothes (atleast where I live, idk about the UK), to wear or as fabric
• set of screwdrivers and bits
• cheap drill, or good used drill
• used laptop
• used oscilloscope
• used all kinds of electronics really; TVs, displays, audio stuff
• thermal water bottle
• Self-defense stuff

Air fryer. If you spend ~300, you can get one that can also be a pressure cooker or small convection oven.

Slow cooker/ crockpot. You can make multiple meals with minimum effort.

Pressure cooker. Lets you cook a lot of cheaper, bulk food faster.

A quality double-sided safety razor. Saves a ton on cartridges. About as easy to use once you get used to it.

Used cast iron pans - last lifetimes and can be used for so much. French press - coffee, tea, chicory, herbs, mushrooms ...

Honestly, I can't think of much stuff at a higher piece point that isn't specialized. Useful things tend to be relatively lower cost.

I carried a leatherman for years, but rarely used it. I find an adjustable wrench, picquick, pliers and box cutter more efficient and easier to use.

Although, I really want cool stuff.

• Second computer monitor

• Immersion blender

• Basic tool kit

• Fabric shaver

Edited to add:

• Clear plastic storage boxes/organizers

• For cooking: non-stick pans, MSG

If you like your hair on the shorter side, hair clippers.

I’ve been cutting my hair for a long time now, and have probably saved thousands from skipping barbers, as well as been able to cut my hair exactly as I like it, and far more frequently/conveniently.

Ultrasonic cleaner. Cleans all the stuff that's hard to get to usually. Also great for glasses.

I got a battery-powered air blower after seeing a YouTube video comparing and reviewing them.

I've always joked about how stupid leaf blower are, but I've found this pocket-sized version really useful.

Cleaning out dust from computers, tower fans, etc, it is amazing.

I also have a small dust buster and this blower gets its filter really clean like nothing else can.

Unlike cans of compressed gas, there's no concern about inhaling anything if I use it indoors, or getting frostbite when the can cools.

An electric pump. I can do bike tires, car tires, camping beds, etc. with full ease.

Chest freezer, vacuum sealer, wired electric impact wrench.

i had bought gas stove called firemaple fms, and its amazing, i always bring it to my camping trips, even to some festivals. Its quite compact

Or dollars, or Euros, or whatever your currency is

In the US; a gun, 2 months of water, 6 weeks of internet, 2 weeks of electricity, 10 days of groceries, 6 days of health insurance, or 3 days of rent. Or, you can buy 5 cases of beer.