This PC emulator is written in Javascript. The emulated hardware consists in the following devices:
32 bit x86 compatible CPU
8259 Programmble Interrupt Controller
8254 Programmble Interrupt Timer
16450 UART
Real Time Clock.
http://bellard.org/jslinux/
PS:最好在chrome里面运行,不然卡死了别怪么提醒咯。