TRNick writes "TechRadar talks to Windows 7's Senior User Experience Designer and discovers the interface ideas the Windows 7 team almost, but didn't put into Windows 7, and the stages various UI features went through to their final form. Quoting: '... The next prototype, in February 2007, was called the Bat Signal; when you moved your mouse over an icon in the taskbar, the full window would pop up on screen, highlighted by beams of light (a little like the Batman signal projected over Gotham City). Bat Signal made it easy to find the right window but it caused other problems: 'sometimes people toss the mouse down to the bottom of the screen when they're typing because they don't care where the mouse is and the Bat Signal pops up and that's really intrusive in their flow.' Bat Signal evolved into Aero Peek in Windows 7; you can hover over an icon to get thumbnails and hover over a thumbnail to get a preview of the window."