If you're looking for the ultimate diner experience, White Palace should be at the top of your list. Career waitresses flirting with cops at the counter. Haggered old men downing plates of steak and eggs. Red vinyl booths. You can pop in and enjoy this experience 24 hours a day, 365 days a year.
The menu is a guide to classic diner foods at its best. You can get any type of food at any time of day, and it's all served exactly how you want it. Don't let the venue's appearance fool you; they know what they're doing. Everything is homemade and created from the owners' own recipes. My favorite: the French toast. I can't really describe why, since it doesn't have any fancy ingredients in it, but it's just the best! Toss in a side of greasy, fatty bacon, and don't bother me while I stuff my face.
I started eating here when the South Loop was still a pile of abandon warehouses with tons of free parking. Now, you'll find that White Palace is quite out of place among the Yuppie moms shopping at the Whole Foods. Parking has become a major challenge, so I'd try to take public transportation.
And if you need further proof of how awesome White Palace is, check them out on "Diners, Drives and Dives" from the Food Network.