HOWTO make a laser cutter for less than 50 bucks

Bilal sez, "I just made a laser cutter that costs less than 50 dollars. The link is to the instructables detailed description of it's construction. I hope this gives you hope for a city completely plastered in intricate stencils impossible to cut by hand."

Here's the list:
1x Laser diodes Ebay Store $36 dollars for 2
2x Old Scanners Salvation Army $10 Dollars each
2x ULN2003 Electronic Connection $5
1x Prototyping board RadioSchack $2
2x 3/8" Aluminum Rod Home Depot $3 each
1x 3/8" Aluminum Tube Home Depot $3
10x Brass Brackets Home Depot $1
1x 2" cube of wood Home Depot $1
A bushel of Patience
Link (Thanks, Bilal!)