What games are you personally attached to? It doesn't even have to be a good game, just one that you feel a personal connection to.
For me it's pic related; it's a CD full of arcade games that my father got for me when I was a kid.
Resident Evil Outbreak. It was my first online console game and it came out just as I was in my transitional phase to adulthood. Highschool was finishing up, first car, first job, college, independence, new friends (some I still talk to, some I don't), even with all this going on I found the time to get online with the 20 other fuckers dumb enough to buy this shit and put in hundreds of hours on the only 5 levels available.