What are some good hobbies to start when life feels boring or repetitive?

Full marks for the A to A

There's been a real resurgence of interest in flying models, which all to the good.
I like my guns too, though strictly legal and home use.
When my mother said "you can't have an airgun", as soon as I flew the nest, it was one of the first things I did.

Some new ones, for next door neighbours rats, and a lovely 1910 BSA Lincoln Jeffries underlever to pick up and sigh. Ancient Webley & Scott pistol for garage target practice and eye, vision, coordination.