As someone who hasn't taken the plunge on an Xbox 360 yet, I've been occasionally checking the official Braid website
for news on the PC version. It had been scheduled for the holiday season but was moved back to February or March so as not to get lost in the blockbuster insanity that was Q4 2008.
Anyway, checking the official blog the other day informed me that creator Jonathan Blow started a contest
this past week. The prize is one copy of Braid
on Xbox Live Arcade to the first 20 people
who correctly identify from what games the 10 screenshots he posted were taken. Apparently if less than 20 people manage to identify all of them he'll pick winners from those who got the next highest score and so on until they've all been given away, so give it your best shot. No word on whether anyone has managed to identify them all yet.
I got #1, 2, 5, and 7 I believe (still a bit iffy on 5.) Most of the shots are pretty difficult--if you don't know right away what game it's from, you're going to have a hard time guessing. Except for #1. Everyone here should know #1. He mentions something about doing another contest after the PC version comes out.
Please refrain from posting answers in the comments. Have fun!
Giveaway: Free copies of Braid (Xbox 360)
[Official Braid blog]