The Crud that collects under the keys in a keyboard. Usually more severe in the keyboards of programmers and webmasters as they tend to spend a lot of time at the the computer and thus eat at their desk. Mainly affecting IBM Model M (clicly) style boards.
Can also be used to gross out Non-Techie people
Bill: want to go to the club?
Bob: No, I've got to clean out my board chow, keys are starting to stick.
Bill: Want to go out to get a bite?
Bob: No, i am just going to have some of my board chow/
Bill: Whats' that?
Bob: The food scraps that collect in my keyboard; Want some?
Bill: *GAG* *HURL* *GAG*