Queued Tasks at a specific time
<p>So, I've got a WCF application that accepts requests to do work at a specific time.  I could have a list of thousands of things to do in the future at varying times.  Is there an existing framework that we can leverage to do this?  The current implementation polls a database, looking for things to do based on a datetime, which smells.  </p>

<p>A few ideas.</p>

<ol>
<li>Timers.  Set a timer when the request comes in that fires are the appropriate time.  This seems like I could have too many threads floating around.</li>
<li>Maintain a list of objects with a datetime in memory, poll this for things to do.</li>
<li>Use a library like quartz.  I have concerns as to whether this can handle the volume.</li>
</ol>
