  Bose condensation of quasiparticles in physical systems of finite size iz
considered for the case of ferromagnetic thin films. It is shown that in
accordance with present-day experimental capabilities which permit one to
achieve densities of long-wave spin excitation of 1018-1019 cm-3, in such films
the formation of condensate of such quasiparticles begins at temperatures T~100
K (room one including). It is found that Bose condensation is accompanied by
scaling phenomenon according to which the main thermodynamic variable is not
the number N of particles but the ratio N/T. This indicates that condensation
of magnons can be observed at relatively low magnon densities. The roles played
by the shape of the spectrum and film thickness are analyzed.
