Respond! is a control panel that brings a limited form of preemptive multitasking to the Mac right now. And itruns on any Mac, 68k or PowerPC, with System 7.0 or later No more waiting for MacOS X or Rhapsody. Even inMac OS 8, if you hold down a menu in the Finder, processes will not continue in the background. With Respond!, youcan be holding down a menu (particularly useful with Sticky Menus in Mac OS 8), or clicking in a the zoom or closeboxes (or the WindowShade collapse box in Mac OS 8), or dragging a window or the thumb of a scroll bar, andprocesses will continue in the background.
System 7.0 or later