Things I have done:
RND 5042, used for $800. Not really a distortion box but tons of heft and color.
Analog heat. Completely obvious choice.
Reamping through my old Yamaha 4-track tape recorder. That can get some truly raunchy results with some saturation.
Cranking preamps and backing off with passive attenuators. My favorite is an Aurora GTQ2, not cheap but good for lots more than distortion. But a cheap pre that distorts surprisingly well is the A Designs P1. A passive summing mixer and a preamp collection can be great fun. RND silk is rad and can be had on their cheaper preamps.
Kemper profiler. Every amp in existence, and nearly indistinguishable from analog distortion.
Guitar pedals. So many great dirt boxes out there, but think about the cheap Chinese clones like mooer. The Rat clone is sick. They cost nothing so you can easily get stereo setups.
Put a clip on a loud phone like an iPhone X, then play it while holding the speaker up to some single coil guitar pickups going into cranked amp, record the result. It’ll be demolished in a way that’ll have listeners scratching their heads. Maybe I should’ve kept that one to myself