1.0 link Rainbow Dash Network http://rainbowdash.net/ adiwan (adiwan) http://rainbowdash.net/adiwan http://rainbowdash.net/notice/4349429 @<span class="vcard"><a href="http://rainbowdash.net/user/796" class="url" title="Cloud Kicker"><span class="fn nickname mention">critialcloudkicker</span></a></span> Mechanical or electronic? A mechanical solution would be an 8-hour &quot;hourglass&quot; that falls down on a scale and it triggers a bell when enough sand is on the scale. An electronic one could be made with a 555 timer IC, a counter, and a buzzer circuit that is triggered when the counter is on the equivalent count of 8 hours. There are plenty other or better solutions that I can't think of at the moment.