Using windows authentication on a peer to peer network to access SQL

I know it's possible to use SQL authentication to access a SQL instance on another computer in a peer to peer network.  Does anyone know if it's possible to access a SQL instance on another computer in a peer to peer network using Windows Authentication?  If so, how do you do it? 

I've tried configuring the SQL instance to grant full access to the user from the 'client' machine, but when you search for "location" in SSMS, the only one that comes up is the machine name of the SQL server instance.  Both machines are connected (I can access folders of other computers in the network).

I'm using Sql Express (2008) and have iis 5.1 running on one of the machines, if that helps.

Thanks,

Sherri
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