You guys have to tell me when my sidebar goes away. I use a laptop with a widescreen, so it's always there for me.
It's usually from posting a video that's a smidge too wide. I usually remember to change the width, but sometimes I forget...
UPDATE: Oh! That was tricky. All the vids were perfectly set to 380 width. The culprit was a little hidden code on the Funny or Die vid setting the TEXT width to 486. Sheesh! And there wasn't enough text to actually take up 486 px, so it wasn't showing up to my eyesight. Tricky bastards.
So remember that, fellow anal retentive bloggers: if you're posting Funny or Die, get under the hood and fix the code.