The Multi-Boot Configuration Handbook

Summary

Configuring a computer to use multiple OSs provides unusual opportunities and challenges. You can expand the range of what you can do with your computer, learn about new OSs, or ease a transition from one OS to another. In availing yourself of these advantages, though, you must ensure that you can use your hardware (or at least be sure that unsupported hardware isn't critical to basic computer functions), design a partitioning system, and get your systems to coexist on one computer.

It's possible to place quite a few OSs on a single computer, but the more OSs you install, the more compromises you're likely to face. My own computer, Nessus, is reasonably well configured. Nonetheless, the fact that it runs so many OSs with so few problems ...