  Over the last few years, numerical models of the behavior of solar magnetic
flux tubes have gone from using methods that were essentially one-dimensional
(i.e. the thin flux tube approximation), over more or less idealized
two-dimensional simulations, to becoming ever more realistic three-dimensional
case studies. Along the way a lot of new knowledge has been picked up as to the
e.g. the likely topology of the flux tubes, and the instabilities that they are
subjected to etc. Within the context of what one could call the ``flux tube
solar dynamo paradigm,'' I will discuss recent results of efforts to study
buoyant magnetic flux tubes ascending from deep below the photosphere, before
they emerge in active regions and interact with the field in the overlying
atmosphere: i.e. I am not addressing the flux tubes associated with magnetic
bright points, which possibly are generated by a small-scale dynamo operating
in the solar photosphere. The presented efforts are numerical MHD simulations
of twisted flux ropes and loops, interacting with rotation and convection.
Ultimately the magnetic surface signatures of these simulations, when compared
to observations, constraints the dynamo processes that are responsible for the
generation of the flux ropes in the first place. Along with these new results
several questions pop up (both old and new ones), regarding the nature of flux
tubes and consequently of the solar dynamo.
