68 byte Christmas Present in BBC Basic

Author: Serato / Finnish Gold
Category: Christmas Challenge
System:   BBC Micro
Language: BBC Basic
Len source code: 103
Len exe file:    69
Len code only:   68
Instructions:
Mount box.ssd file, or import $.BOX to a fresh ssd. MODE 1 for best display.
LOAD"BOX" and RUN
Description:
The first line is printed directly, using TAB() to indent.
The rest of the box is calculated implicitly by iterating X and Y from -9 to 9
and testing each for MOD 9 = 0. These boolean results are combined with boolean
operators to form a result from -2 to 1. This is subtracted from 2 to give a
range 1-4 which selects a character using MID$("! -+").