A fat sandwich is a submarine-style sandwich variety that is characterized by being overstuffed with calorie-laden, fatty, fried ingredients such as gyro meat, chicken strips, fries, and mozzarella sticks. These supersized sandwiches originated at Rutgers University in New Brunswick, New Jersey, where they were originally served out of so-called Grease Trucks which were lined up on College Avenue, satiating the hunger of numerous students, mostly after a night of heavy drinking.

It is believed that the first fat sandwich was invented in 1979 and was called the Fat Cat, consisting of a cheeseburger topped with french fries. Today, there are a number of variations including the Fat Darrell, the Fat Knight, the Fat Elvis, the Fat Lady, and the Fat Romano.

An egg sandwich is an internationally popular breakfast staple that typically consists of eggs between slices of bread. The sandwich is usually enriched with cheese, and it's often complemented with some kind of meat such as cold cuts or sausage meat.

Nowadays, there are numerous variations on this sandwich, but it is believed that one of the first egg sandwiches was made in the early 19th century in East London by street vendors who wanted to earn some money and feed the hungry factory workers in the process. 

Smörgåstårta is a Swedish layer cake consisting of sandwiches: slices of white or rye bread, toppings, and fillings, frosted with cream cheese, mayonnaise, yogurt, or a combination, and garnished with various vegetables. Traditionally, smörgåstårta follows the smörgåsbord all-in principle: caviar, pâté, cold cuts, shrimp, smoked salmon, cheese, eggs, vegetables, only some of it or all of it together, there are virtually no limits.

This Swedish staple is ideal for parties and celebrations, visually reminiscent of a cake, but with the flavors of a really filling sandwich. The cake is also popular in Estonia and Finland. Interestingly, it has been found out that some of the policemen in Sweden asked for smörgåstårta as a bribe, acting as further proof of the cake's enormous popularity.

Trzesniewski brötchen are a type of open-faced sandwich emblematic of the Viennese buffet Trzesniewski. The base of this morsel-sized belegte brote is rye bread cut into a specific rectangular shape, which is then covered with various spreads and toppings.

Some of the more popular choices include bacon with egg, salami, tomato, smoked salmon, mushrooms, and paprika. The number of varieties is finite and currently stands at 26, each meticulously prepared according to the recipes that have gone virtually unchanged for more than a hundred years of Trzesniewski history. 

Torta Cubana is a Mexican sandwich filled with a variety of meats and sauces, a meal that is different from one vendor to the next. It was invented in the 1950s on Calle Republica de Cuba in Mexico City, when a cantina cook first started serving tortas with everything he had available.

The sandwich quickly gained popularity and got its name from the street where it was first made. Torta Cubana should not be confused with the popular Cubano sandwich, as the two have nothing in common except their similar names.

Submarine sandwich consists of a long, split bread roll, filled with numerous ingredients such as meats, cheeses, sauces, vegetables, and seasonings. Depending on the regional variety, the sandwich is called differently throughout the United States.

In the Midwest and California, it's grinder, in New York and Northern New Jersey, it's hero, in Delaware, it's sub, and in Baltimore, South Jersey, and Philadelphia, it's called a hoagie. Around New Orleans, it's known as po'boy, and in Maine, it's Italian sandwich, even if it has nothing to do with Italy. 

Chlebíčky are small, open-faced sandwiches originating from the Czech Republic. Although there are many open-faced sandwiches throughout the world, chlebíčky are unique because of their unusual combination of toppings, a variety of flavors, and careful arrangement and presentation.

The sandwiches usually consist of thin slices of white bread topped with spreads such as potato salad, cream cheese, and lobster paste, along with ingredients such as tomatoes, salmon, capers, Brie cheese, cooked ham, or pepperoni. The original chlebíčky was invented by Jan Paukert at the beginning of the 20th century in Prague, and it consisted of Prague ham, pieces of a hard-boiled egg, a slice of Emmental cheese, tomato, Hungarian salami, and potato salad. 

Sandwiches de miga are prepared with crustless white bread, and they can consist of two or more bread slices per sandwich. It is believed that they developed under strong European influences, primarily British and Italian. The most common variety of the sandwich is made with mayonnaise, cheese, and ham, but there are no restrictions concerning the possible fillings.

Although sandwiches de miga are usually consumed as an afternoon snack, they are also a staple at parties, celebrations, or family gatherings. A common variety is called a tostado – a toasted sandwich de miga that is traditionally served warm. 

Tramezzino is a popular Italian triangular sandwich made with chewy, crustless white bread and various fillings such as mayonnaise, tuna, prosciutto, and cheese. It is believed that the first tramezzino was invented in 1925 at Caffè Mulassano in Turin.

It soon became incredibly popular, especially in Venice, where it's often enjoyed with a glass of Spritz. Today, there are numerous varieties of tramezzini, and they can be found in cafés throughout Italy, although pre-packed varieties that can be bought in supermarkets are also quite common.