Many Mac users don’t know this, but Microsoft (of all people) offers a very useful and free utility for controlling your Windows based PC, from the comfort of your Mac. It’s called Remote Desktop Client.
Once configured, you can login to your PC desktop from you Mac. You’ll have full access to everything on your PC. Your Mac keyboard will work just fine with your Windows apps, even keyboard shortcuts work, but you need to use the control key just like you would on your PC. You can even use a 2-button mouse and Windows will respect right-clicks.
Remote desktop client won’t allow you to totally get rid of your PCs keyboard, mouse, and monitor because you still need to do the initial login directly on your PC, but it may allow you to move that PC to a less accessible location. It’s also not a good solution for gaming, or other processor or video intensive tasks because it’s a little slow, but it is a great solution for simple tasks, like moving files back and forth, or checking web sites you’ve built.