  A toy top is defined as a rotationally symmetric body moving in a constant
gravitational field while one point on the symmetry axis is constrained to stay
in a horizontal plane. It is an integrable system similar to the Lagrange top.
Euler-Poisson equations are derived. Following Felix Klein, the special unitary
group $\rm SU(2)$ is used as configuration space and the solution is given in
terms of hyperelliptic integrals. The curve traced by the point moving in the
horizontal plane is analyzed, and a qualitative classification is achieved. The
cases in which the hyperelliptic integrals degenerate to elliptic ones are
found and the corresponding solutions are given in terms of Weierstrass
elliptic functions.
