Jeroen Breebaart has released Barricade, a simple yet effective brick wall limiter. It has separate controls for gain adjustment, limiter release time, and variable softclipping for extreme 'overs'.
Barricade is available as a VST effect plugin for Windows and it is free.
Jeroen also recently updated Omnisone to version 1.05, offering improved control of stereo width (the conventional side-signal gain) and ambiance processing, and support for 192 kHz sampling rates.