The amount of times I've managed to burn myself/the furniture/ the cat with my hair straighteners is slightly embarrassing, (OK, I don't have a cat). Still, second degree burns on the butt are never fun, so I think this cheap as chips heat proof mat could be a wise investment. Available in sparkly pink or black, to costs a mere £7.99 from Parma Gray and can cope with heat up to 250 degrees.
It's made out of recycled materials, so is kind to the environment and will protect your furniture from burns. The mat changes colour when the tool is hot, meaning you know when to pick up and when to avoid, and you can use it to wrap the straighteners in if you have to rush out with them.