I've been toying with the idea of using a file as a queue instead of a database table for use with my Enhanced Threading Framework.  This has been challenging and I am nearly complete.  I can't say at this time if it is faster or slower, better or worse, a breakthrough or waste of time.  I got the idea a few weeks ago to try this and now I can't stop.  I will post more details once I have some results.  Right now I am having an issue running out of memory, which means somewhere either myself or SSIS is not properly disposing of an object or two.  I hope to have an blog post within the week.