Al,

>>COM+ Queued Components might be another option.
>
>Do you have any good URLs for an overview of this? Do you know if it's supported down to W98 (and preferably, W95)?

There is ample documentation on MSDN for MSMQ (Microsoft Message Queue):

http://search.microsoft.com/search/results.aspx?View=msdn&st=a&qu=MSMQ&c=0&s=1

In addition, you may want to check out Rick Strahl's table-based async classes, described in this article about async web routines. You might adapt his stuff to your needs, which should run on any OS:

http://www.west-wind.com/presentations/wwAsyncWebRequest/wwAsyncWebRequest.htm