Is it possible to change the BorderStyle of a form?

I am making a sort of docking system so that I can either dock forms (using the SetParent API to bind to a picturebox) or show the form as floating.

It looks stupid when the form does still have the titlebar when docking, and it also looks stupid when it's floating and there is no titlebar.

I found out it is impossible to change the form's Borderstyle from 5 (toolbar) to 0 (none) at runtime. Is there any way I can do this anyway?