Carsten of Langå, Denmark, one of the longtime YaBB developers and BoardMod developers has released a new mod on BoardMod for YaBB 2.2.  The new release is called CSS Buttons for YaBB 2.2.  Carsten states:

This mod will add "soft coded" css driven buttons to your board and give you the option to change the graphics and text attributes for buttons in the css wysiwyg editor.

This mod and many others can be found on BoardMod's BETA Mods for YaBB 2 board.