Thanks to a previous poster, the problem actually comes from the MediaDirect
AddIn that Dell installs by default.

Full quote:  "Ok, after more digging this morning, I did confirm that this
is related to
the OutlookAddin from Cyberlink.  This addin is for the MediaDirect program
included on Dell systems.  The issue is that the addin is pulling your
calendar and contact data over for use in MediaDirect (notice any lag/CPU
spikes while you're in Outlook?).  If you're not looking at that info in MD,
then you can remove this addin by going to the setup here:

Program Files\Dell\MediaDirect\OLAddin\

Run the setup file and remove the addin.  I was not able to disable the
addin through Outlook, so this is the route I had to take.  I've just tested
this in Outlook 2007 by saving attachments and creating them, and no more
folder creation.  Also, I've noticed a difference in the lag on my typing.

I didn't find this solution on Dell's support site--I found it on the
Notebookreview.com forums and it seems to date back to November 2006.
Someone on there noted they talked to Dell support and it was recommended to
remove MD until a fix was out.  I bought my laptop in March 2007 and it's
still doing it, so I guess it's not addressed.  But, good news is that you
can just remove the addin. "