The legality of no-cd patches is questionable. Some gamers use the patches to use warez copies of games. Plus it can be a hassle to have to search for a no-cd patch for a specific game. There is an easier solution.
Virtual CD software is a good solution for not having to put CDs in the drive to play games. The software keeps a copy of the CD on your hard drive, and creates the file so the computer sees it as a CD-drive. This allows you to play your favorite game without having to hunt for the CD. Another positive about virtual CD software is that you can keep your software in a safe place and not worry about the disks getting scratched or lost.
Game Jackal is another option. It is similar to virtual cd software. However, it is made specifically for games and does not use a lot of hard drive space.
Virtual CD Software: