Chess game showing which moves the computer is considering

I stumbled across this chess game this morning
http://transition.turbulence.org/spotlight/thinking/chess.html
Every time you make a move, it shows you what moves the program is considering. The brighter the lines are, the better the move.

On the "About" page, they say this:

The chess engine we built is simple and uses only basic algorithms from the 50s (alpha-beta pruning and quiescence search). The program's unconventional initial moves may raise eyebrows among experts: we did not give it an "opening book" of standard lines since we wanted it to think through every position.

Although I wouldn't recommend using this if you actually wanted to complete an entire game in less than a couple of hours, it's pretty cool seeing all of the moves being analyzed in real time.