Starz 2 bucks a month for 2 months, AppleTV free for a month and various others
A tip for managing promo deals is using Privacy.com (not sponsored, just a happy customer). You can set a virtual credit card and set a monthly limit on the card. So, when the introductory price expires and the price increases, it will decline. I never remember to cancel during promos.
Most streaming services let you cancel and live out your current plan (just like Channels).
So just cancel as soon as you subscribe.
But some are promo rate for multiple months. Example Starz is $1.99/mo for 2 months. Then increase to $10.99. With Provacy you can set maximum monthly limit $2. Then it will auto decline when the rate increases. Especially useful for things that have a promo rate for things that are longer then 1 month.
privacy.com is great, I use it. The bad part is you have to associate it with your debit card, can't use credit cards unless they changed it recently.