I just realized that running sushi is the best fast-food ever. (Yes, I have strong opinions weakly held):

• You get you food in small chunks, so you can stop at any time and still don’t feel like you’ve wasted food
• You have a great variety of food and you can look at it before taking (rather than just looking at a picture in the menu and wondering how the real thing will look like)
• It is most probably healthier than other kinds of fast-food
• It is neither hot nor cold, so you can eat it right away (you don’t have to wait for it to warm up or to cool down)
• You don’t have to order! The last thing you want to do when you are hungry is to stare at food and wait

PS. If you are Cluj (Romania) you can check out the Wasabi Running Sushi. As far as I know they are the only running sushi in Romania!