Jeff Larson has released Mobius, a stand-alone application and VST effect plug-in for the real-time creation and manipulation of audio loops.
Mobius has functionality based on the venerable Echoplex Digital Pro with Loop IV software; it is not a complete emulation, but it does implement many of the Loop IV features, as well as a number of useful new features. Mobius is essentially 8 synchronized stereo EDPs with the ability to copy loops and timing between them. Extensive MIDI and computer keyboard control is available. Audio content may be saved to and loaded from files.
Mobius is free and is available for Windows.