Check out this little Sony UX490 UMPC that has been hacked with a voice-capable HSPA modem and quad boot options for Windows XP Pro, Windows Vista Business, Windows 7 Ultimate and Mac OS X Leopard 10.5.7.
I don’t know why you would need all those different operating systems for such a little device but still, it’s a quite an achievement. I want one.
Only thing missing, what happened to my ol’ linux?