"Imitation is the sincerest form of flattery"

Windows - Others

Windows OS - Xerox and Apple
IE - Netscape
Doublespace - Stacker
System Restore - Norton GoBack
Word - WordPerfect, Multimate
Excel - Lotus 123
Media Player - RealPlayer, WinAmp, QuickTime
Compressed Folders - WinZip, PkZip, ARC
Disk Defrager - Norton Tools
ScanDisk - Norton Tools
LiveCare - ALL of the older Virus/adware checkers
Outlook/Express - Forte Agent / Lotus Notes
PhotoStory/Movie Maker - Proshow/Proshow Gold
Remote Access - Norton pcAnywhere
Messenger - Trillian, Gaim, AOL
Aero Theme - Beryl from Linux (actually a stretch... Beryl, although unstable at this point, is technically light-years ahead of Vista)

and probably others....

Microsft.... the Pot calling the Kettle Black.....