here is a sketch:
db.define_table('what_to_see', Field('html_code', 'text'))
db.define_table('what_to_see_queue', Field('user', db.users),
Field('when_allowed_to_see', 'datetime'))
if user_not_in_queue:
if last_user_allowed_time + 5minutes < time_now:
when_allowed_to_see = time_now
else:
when_allowed_to_see = time_now
add_user_to_queue_with_his_time
if when_allowed_to_see > time_now:
display_refresh_in (when_allowed_to_see - time_now)
and_a_script_to_refresh_page_after_a_period_of_time
else:
display_html_code
delete_user_from_queue
