This paper presents some recent results in the area of application of fractional order system models. After the introduction to
the dynamic systems modelling with the fractional order calculus the paper concentrates on the possibilities of using this approach to the
modelling of real-world phenomena. Two examples of such systems are considered. First one is the ultracapacitor where fractional order
models turn out to be more precise in the wider range of frequencies than other models used so far. Another example is the beam heating
problem where again the fractional order model allows to obtain better modelling accuracy. The theroetical models were tested experimentally
and the results of these experiments are described in the paper.