Here's a trailer for the next Fallout: New Vegas DLC installment, Old World Blues. It looks set to be the most comedic chapter of the New Vegas saga, and I dare say its focus on science-themed humor might be inspired a little by Portal.
Just a little.
It certainly looks good for a laugh, and is the most appealing of the DLC as far as I'm concerned. Definitely looking forward to getting it on July 19.