Various known composite particles are scalar bosons, e.g. the alpha particle and the pi meson. Among the scalar mesons, one distinguishes between the scalar and pseudoscalar mesons, which refers to their transformation property under parity.
One very popular quantum field theory, which uses scalar bosonic fields and is introduced in many introductory books to quantum field theories for pedagogical reasons, is the so-called φ⁴-theory. It usually serves as a toy model to introduce the basic concepts of the field.