When I left NY to Toronto, one thing I missed was hanging out at Tom's Diner. Then (around the time of TIFF), one of those page sixers took a photo of Rachel Bilson & Adam Brody (aka Summer & Seth from the OC) eating at Flo's. Eureka! A diner just a few minutes walk from my place. However, I associate diners with late night grub. And despite having posted hours till 9 or 10 pm, on light nights this place just closes early, unannounced. The food is okay, but really pricey and nothing special. There's some attempt at making it look like an old-school diner, but I still missed Tom's.
One nice thing is that in the spring/summer you can sit outside and the outdoor seating is really great. However, don't even try to climb the spiral staircase in the winter, since it's icy as hell. Instead, just go inside and take the elevator up a level.