Is there anyway to get Second Sight to stretch out to 1680 x 1050(16:9, on my HDTV)?

Might try this . . . =)
"The game unfortunately stretches and I don't see any options for FOV or aspect ratio."
Edit: seems I remember you needed to turn V-sync off as well. . . could be wrong on that.

Try using scaling. If you have a nVidia graphics card, go to the nVidia Control Panel, then choose adjust desktop size and position. From there you can set the scaling. Try different options, see which one suits you the most.
Should be somewhat similar if you have an ATi graphics card.

I've an ATI card, and I see no scaling settings in the Catalyst Control Center.

Try these instructions . . . =)
"Go to the ATI Catalyst Control Center (by right Clicking on the desktop ,display, control center tab), On the top left there will be a drop down menu, click on it and choose "Desktop & Displays" On the bottom half of the screen Right click on the icon of your display, and choose "Configure," On the next screen choose "Scaling Options" tab you can then slide the rule all the way to 0% scaling and you should see the screen change to cover the full monitor"
Edit: this page has some images

Okay, so kind of like the Overscan options in AmigaSYS. So, do combine scaling with the editing of the secondsight.cfg?