The inexpensive sushi source: Rice Chef on Kearny.
All around the Financial District of San Francisco you see little packages of wrapped sushi, such as nine California Rolls. Don't pick them up at Lee's Deli. Go to the source: Rice Chef at 329 Kearny Street.
Not to disparage Lee's. Lee's makes the fastest sandwich in the West, with a heap of turkey. But for a sushi snack, the price is lower and the selection greater at Rice Chef where they make it.
It's the sliced-roll kind of sushi, not the fish-on-top kind. There are several vegetarian salad roll varieties. The meat selections are only spicy tuna, fake crab, and breaded chicken.
My favorite item they make is a salad of slightly steamed spinach and cabbage with soy sauce dressing. This is my kind of fast food, healthy and interesting. Second favorite is the cold soba noodles, also wrapped and ready to go.
They have udon and rice bowls, such as the "Vege Terian" you see at Lee's. Their oyakudon -- egg and chicken over rice -- is warm and hearty. If you order the seafood curry over rice, you'll say to yourself, "Oh, this must be what cafeteria food tastes like in Japan."
They do not have miso soup or tea. Are you shocked? They do have big party trays for about $30 if you have an office party.
And, if you've read all of this message, I've saved some good news for the end. At 4:30 p.m., they cut their prices by 50%. So, depending on your work schedule, your lunch or dinner can be only $2 or $3. They're open only weekdays, as far as I know.