Here's a really ugly implementation that only requires 16 AND gates, one 8-input OR and an inverter:
**broken link removed**
The first OR output ("A") says "any input was selected" (which will cause output 1 to be turned on by any AND);
the other output ("B") says "no input was selected" which will cause output 2 to be turned on by any AND.
(I got the two outputs reversed; O1 was supposed to be the one turned on first. Oh, well.)
(Now that I've drawn this, I realize you probably don't need all them diodes in front of the OR ...)
25 cents to anyone who can simplify this mess.
You could probably do all this with less hardware by using a microprocessor with 8 inputs.