Rollerball pens employ the same ballpoint mechanics, but with the use of water-based inks instead of oil-based inks.Compared to oil-based ballpoints, rollerball pens are said to provide more fluid ink-flow, but the water-based inks will blot if held stationary against the writing surface. Water-based inks also remain wet longer when freshly applied and are thus prone to "smearing"—posing problems to left-handed people (or right handed people writing right-to-left script)—and "running", should the writing surface become wet.

Some ballpoint pens use a hybrid ink formulation whose viscosity is lower than that of standard ballpoint ink, but greater than rollerball ink. The ink dries faster than a gel pen to prevent smearing when writing. These pens are better suited for left-handed persons. Examples are the Uni-ball Jetstream and Pilot Acroball ranges. These pens are also labelled "extra smooth", as they offer a smoother writing experience compared to normal ballpoint pens.

Because of a ballpoint pen's reliance on gravity to coat the ball with ink, most cannot be used to write upside-down. However, technology developed by Fisher pens in the United States resulted in the production of what came to be known as the "Fisher Space Pen". Space Pens combine a more viscous ink with a pressurized ink reservoir that forces the ink toward the point. Unlike standard ballpoints, the rear end of a Space Pen's pressurized reservoir is sealed, eliminating evaporation and leakage, thus allowing the pen to write upside-down, in zero-gravity environments, and reportedly underwater. Astronauts have made use of these pens in outer space.

Ballpoint pens with erasable ink were pioneered by the Paper Mate pen company. The ink formulas of erasable ballpoints have properties similar to rubber cement, allowing the ink to be literally rubbed clean from the writing surface before drying and eventually becoming permanent. Erasable ink is much thicker than standard ballpoint inks, requiring pressurized cartridges to facilitate inkflow—meaning they can also write upside-down. Though these pens are equipped with erasers, any eraser will suffice.

The inexpensive, disposable Bic Cristal (also simply "Bic pen" or "Biro") is reportedly the most widely sold pen in the world.It was the Bic company's first product and is still synonymous with the company name. The Bic Cristal is part of the permanent collection at the Museum of Modern Art in New York City, acknowledged for its industrial design. Its hexagonal barrel mimics that of a wooden pencil and is transparent, showing the ink level in the reservoir. Originally a sealed streamlined cap, the modern pen cap has a small hole at the top to meet safety standards, helping to prevent suffocation if children suck it into the throat.

Multi-pens are pens that feature multiple varying colored pen refills. Sometimes ballpoint refills are combined with another non-ballpoint refill, usually a mechanical pencil. Sometimes ballpoint pens combine a ballpoint tip on one end and touchscreen stylus on the other.

Ballpoint pens are sometimes provided free by businesses, such as hotels and banks, printed with a company's name and logo. Ballpoints have also been produced to commemorate events, such as a pen commemorating the 1963 assassination of President John F. Kennedy. These pens, known as "advertising pens," are the same as standard ballpoint pen models, but have become valued among collectors.

Sometimes ballpoint pens are also produced as design objects. With cases made of metal or wood, they become individually styled utility objects.