AdSense across different sites

My question is this, If I signup for Adsense can I use it on multiple sites of mine. My bigger issue is one of my sites is a poker site, google says they don't allow those sites, but I have seen tons of them using adsense, so I was wondering if I sign up with one of my other sites and just add it to my poker site. I'm sure google could find out, they only thing I fear is them banning my site from the index. I'm just not sure how they can say they don't allow gambling sites, when I see them and directories that have gambling content use adsense all the time.

If not, does Yahoo have a similar option, Others?

Thanks
Bones

Once you are accepted into AdSense, you may use it on any of your sites. You are expected to comply with the TOS with all uses. If in doubt, ask the AdSense team via e-mail. They are pretty responsive IMO.