Have a look at Squid. Its not exactly an EZProxy alternative but it may 
fit the need here.

Chuck

On 8/14/10 1:05 PM, phoebe ayers wrote:
> Hello all,
>
> Are there any open source proxies for libraries that have been
> developed, e.g. an open source alternative to EZProxy or similar? I'm
> working with a non-profit tech foundation that is interested in
> granting access to a few licensed resources to a few hundred people
> who are scattered around the world.
>
> thanks,
> Phoebe
>
>