battery life?

just wondering. how long can i drive if my alternator isnt working, on just a fully charged battery? with nothing on in the car, how many miles you think i could go.

not to far. no sure how far though. i know when i lost my belt in a work van i drove for about 15 miles like that, and the battery was just about drained and the temp was getting really hot lol but it made about 15 miles.