Can I do this
 

Could I cash out all my chips, uninstall my poker room software, sign up under a new name and get a bonus for a first time deposit using the same software, reinstalled?

Why dont you try it.

But it wont work

It won't work because there are some permenant cookies on your hard drive that won't disappear. Though if you reformat the computer you could do it. Or another option is to sign up on a different computer in your household. Though this may even violate the T&C of the poker site.

I don't think it would allow you to - has something to do with the IP address