Okay, so you can't take your dog to your favorite movie theater perhaps, but you can take him with you to most drive-in's!
Rules for having your dog at the drive-in are not anything extreme. Most theaters will require your dog be on a leash whenever he is out of the car. Picking up after your pooch is also the requirement at all drive-in's that allow dogs, and common courtesy. The last rule to be sure to follow is to make sure your dog is quite. My dog will usually watch TV and bark at any other dog or animal that comes walking across the screen, so he will not be joining me at any movies anytime soon.
Check your local area to find pet-friendly drive-in's and be sure you know the rules before you go!