Using 2 USB lightguns, is it possible?

[Timstuff]

I know that USB lightguns work by connecting to the USB port and the monitor out on the back of your PC. But can you hook up two at the same time? And if so, how? Do you need to have them both plugged into the monitor out, one ontop of the other, or do you only need to have one connected to the monitor out? Does using two lightguns even work at this point?

The reason why I'm curiouse, is because I've recently become interested in the prospect of making my cabinet lightgun-enabled. And the reason for that is that I found a website that sells the ActLabs USB lightgun for only $32. 

http://www.ztnetstore.com/product_info.php?ref=8&products_id=28&affiliate_banner_id=1

[LPZ]

Item currently out of stock...

[Timstuff]

Aw, figures. Liksang's Virtual Gun is out of stock too.

http://www.lik-sang.com/info.php?category=0&products_id=1429&

I don't even know how much it costs, but it looks like the most promising of the three guns that Retroblast reviewed to me (ActLab's design seemed decidedly sissy to me). You'd think that these people would re-stock once in a while...

[LPZ]

Act labs is planning on another run of their gun.  Get on the list if your interested.  Prices are a little bit more than last time though.