Portal

[Lkr]

I bought the Orange box for Episode 2, Portal, and TF2.

[Pilot_51]

I bought it for all of those too, but mostly for Episode 2 and Portal.
Portal was so incredibly hyped up that it quite possibly convinced me to buy the Orange Box, it was the first thing I played when I installed everything.
Episode 2 was important for the continuation of the HL2 story and I sort of consider it the frosting with Portal being the cake. (I don't really like frosting that much, which means Portal is better)
I never really cared about TF and I sucked pretty bad when I gave TF2 a run for about a week.
I wasn't about to pay full price when it includes two games I already have and one I wouldn't even pay $10 for alone, so I got it from eBay for about $20 cheaper (the price of Episode 2 alone).