10 PRINT CHR$(205.5+RND(1)); : GOTO 10 in PHP (or anything else, for that matter)
Since this has been migrated to codegolf...

PHP 30 bytes

&lt;?for(;;)echo rand(0,1)?~Ð:~£;


The Ð is character 208, and the £ is character 163.

Sample usage (on a Windows box):

color 18 &amp; php maze.php


Produces something similar to:



It works best with a monospace font that is exactly square (here I've chosen the standard system font 8x8). To go back to your default color, you can type color again without any parameters.