Look me up when you're in town.
When you next come to my town, try to find me (and we will get together). (A vague and perhaps insincere invitation.) Bob: Nice to see you, Tom. Bye now. Tom: Yes, indeed. Look me up when you're in town. Bye. Sally (on the phone): Bye. Nice talking to you. Mary: Bye, Sally. Sorry we can't talk more. Look me up when you're in town.