Television

To be specific, got half off my annual grocery delivery this way. I've also read that it works for some TV subs.

Another fun tip: Some companies have their chatbots programmed to offer additional deals for items already onsale, so next time you're going to make a big purchase, be it a mattress, computer, or whatever, just open the chatbot and say: "Hello, I'm interested in x item. Are there any additional deals or sales going on?"